Seed Collection at the Russell Prairie Near Lake Livingston Saturday, August 29 Join Mercer Society Grower Becky Mills and Mercer Botanist…Read more of this >>
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Sideoats grama (Bouteloua curtipedula) is the official State Grass of Texas, found in every bioregion in the state.
The following is a revised and updated of the classic article written some years ago by Bob and Mickey Burleson of Temple, Texas. It details some of the methods they have had success with in replicating the native Blackland Prairie vegetation on their Blackland farm in Bell County, Texas. Bob served on the Texas Parks and Wildlife Commission and is largely responsible for the existence of a resource management section within that department. Mickey is a founder of the Texas Nature Conservancy, initiated their stewardship program and was influential in TNC’s early priority on Blackland Prairie preservation. Both Bob and Mickey were founding members of the Native Prairies Association of Texas and have reconstructed a prairie from scratch.
To go into great detail would take volumes, but we hope that this guide in outline form will at least get you started in the right direction. Note that at the end are appendices that give specific ideas for planning your prairie, fighting woody invaders and burning your prairie.
The Blackland Prairie is one of the major land resource areas of Texas. It is a strip of dark clay soils varying in width from 15 to about 50 miles, extending in a north-south direction from just east of San Antonio to the Red River in Lamar County. It is now one of the most fertile and productive agricultural areas of Texas, but when European man first saw this area it was a climax grassland, a tallgrass prairie, with a tremendous diversity of plant life. It was among the early areas in Texas to go under the plow, because of its deep soils and high fertility, and was never really adequately studied as a unit by botanists. Now, the original Blackland Prairie exists only in books and in small and widely scattered remnants, such as cemeteries, odd field corners, prairie hay meadows of old German and Czech farmers, and along railroad rights-of-way. Only a very few large and reasonably unaltered segments are left, and substantially all show the effects of either invasion by woody plants, invasion by weeds and exotics, or elimination of many of the original species by herbicides, excessive grazing or improper haying or burning practices.
The Grand Prairie lies just to the west and north of the Blackland Prairie, and is typified by the area between Fort Worth and Decatur, for example. The vegetation was very similar to that of the Blackland Prairie, but the Grand Prairie soils are generally more shallow and the rainfall averages slightly less than in the Blacklands. Both soils were derived from limestones, and the plants from one area will pretty well grow in the other. However, the Grand Prairie was more of a mid-grass prairie than a tallgrass prairie, and was more suitable for ranching than farming. Therefore, there is more of the Grand Prairie left for study today because it was not an early victim of the moldboard plow. The Grand Prairie forms the resource base for the ranching industry from Central Texas to near Wichita Falls, excluding the sandy soils of the Cross Timbers region.
Replicating a prairie simply means duplicating or recreating it in as nearly a natural form as possible. Obviously it is not possible for us to do in a few years what it took nature tens of thousands of years to do, but we have found that by hard work and study we can plant and grow acceptable “prairies” that we hope eventually will develop again into the climax grasslands that so amazed the early travelers through this region of Texas.
In general, we feel that the following are essential items:
(a) Land, preferably five or more acres, that can be permanently devoted to this use. We started with a tract of 100 acres out of a much larger farm, about 40 acres of which was “wornout” land not suitable any longer for row crops. We devoted this wornout land to the prairie project, and later expanded into the better land as we could afford to take it out of row crop production. Prairies can be created on much smaller plots, including yards, gardens and “pocket prairies”, but it is better to have many acres so that you can get a full plant and animal community going, strong enough to resist invading trees, weeds and grasses from outside. Ideally, a tract of 500 to 1,000 or more acres would be great, but out of the reach of many.
(b) Time to collect seeds, mainly by hand at first, from roadsides and native prairie remnants in your area. We worked nearly every weekend for a year to collect the several hundred pounds of native wildflower, forb and grass seeds that we used in our first plantings, and it was nearly all collected by hand. Later, we built pull-along seed strippers and modified a small pull-along combine, to speed up the seed harvest.
(c) A small tractor and shredder, or access to one, to mow and control competitive weed growth during the first two years of the project. A tractor of about 40 h.p. works well. It is not essential in all cases to mow to control the competition, but it speeds the establishment of a good stand better than anything else, and when you work hard for seed, you don’t want to waste any of it in competition with weeds.
(d) Rain and good luck! Almost everything else can be improvised, rented or borrowed. The true cost of anything is the amount of your time that you must exchange in order to obtain it. Prairies don’t cost a lot of cash, but they are expensive in respect of time, and there is no point in getting involved with them unless you are willing to see it through to the end. It usually takes at least two years, sometimes four or five, to see your labors bear fruit when you are dealing with native grasses and forbs on larger tracts. You will not know what or when to collect at first, and will not know what you are looking at. At the beginning you will be wandering around in remnant prairies just looking, starting with the first growth of plants in the spring, and seeing what comes up, what it looks like in early stages of growth, what it develops into, and when and how it flowers and bears fruit. If you read widely in the literature that is available on prairies, you will educate yourself as you go, and soon will know which plants “belong” and which do not. Concentrate on perennial species, not weedy annuals. By spending successive weekends in prairie plots, you will soon get a feel for the total plant community in the prairie, and then, as you see members of this community blooming on roadsides and in waste places, you can add to your inventory of seed sources. No degree in botany is required, and with the many books that are available to help you in your first efforts at plant identification, any intelligent person can become a pretty fair lay botanist with respect to the native prairie plants of his or her area.
The seeds of grasses are often treated differently from those of the forbs (wildflowers and legumes) so we will discuss each separately.
(1) Forbs and legumes. These plants flower and bear fruit at three main seasons of the year. The cool-season forbs usually grow as a winter rosette, close to the ground, and then flower in early spring and set seed in late spring. Then, a second group of flowering plants appears and blooms on into summer, setting seed in mid to late summer. Finally, there are a number of prairie plants that slowly grow from spring to fall, and then bloom and set seed in the fall. You will therefore have three main collecting seasons, in about May, July, and October. These are good “rule of thumb” months for collecting seed of wildflowers in Central Texas, but since the time of blooming and seed set is variable, according to rainfall, etc., you usually collect seed from early May all the way through until frost, with peaks in these months just mentioned. Most wildflower seeds go through stages of maturity, starting with young seed, green and watery, progressing to a “milk stage” when the seeds look like “seeds” but are filled with white liquid, then progressing to a “soft dough” stage, and finally to a “hard dough” stage, at which time the inside of the seed is firm and mature, usually white or tan in color from stored starches. As a “rule of thumb”, you are wasting your time, and wasting the plant, to collect seed before it reaches the hard dough stage. If the seed is in the hard dough stage, you can generally expect the seed to be mature even if the flower head is still a bit green. Native plants usually mature seed rather rapidly, and the annuals are particularly hardy in this respect, so that you can get good seed several days before the flower head finally dries up and shatters. The way to recognize “ripeness” is to start with the plants in full flower, and then occasionally pluck a flower or seedhead and check it out during the growing season. Use a magnifying glass and a penknife or your thumbnail to see what stage of development it is in. After some experience you can pretty well tell from external signs alone whether the seed is mature or not in most of the more common wildflower species. As you collect your seeds, first dry them thoroughly. We usually dry them in large paper grocery sacks, or shallow, open boxes, on a shelf in a well-ventilated area. Don’t pack them in the sack, and keep the layers shallow. Moisture and the results thereof are harmful to the life of the seed, and so is excessive heat. After the seeds are dry, they can be combined in a larger “breathable” paper bag for storage. Some folks spray them with an organic insecticide to prevent weevil and moth damage, but we usually do not. In larger batches, a closet-size moth crystal block can be placed in the closed bag to control insects. Since you are planting a mixed prairie, there is no need to separate the seeds or clean them. Just collect mature seeds and dry them properly. They will all be planted at once in a mixture, so they can be stored the same way. Once wildflower seeds are mature, they often shatter quickly. As the petals drop from the flowers and the seeds mature, you will need to watch the “crop” carefully. As soon as they are mature enough to collect, do so without delay. You may wake up and find that a rainstorm or strong wind has scattered the seeds, and you will have another year of waiting for that species. Many prairie flowers are showy when in bloom, but almost become invisible when the petals drop. It is a good idea to keep notes of the location of these plants, and to mark them with slender stakes or with surveyor’s tape to help you locate them after the petals fall. With experience, you can spot them anyhow, but in your beginning stages you will need to mark them in some way. A good rule is to plant all wildflower and forb seeds in the fall of the year. October is a great time. You can hardly go wrong with fall planting on almost any of the prairie wildflowers, even if they do not germinate until spring. Most of them will benefit from shallow planting, not more than one-half to three-fourths of an inch deep. If you mix them with the grass seed and plant with a drill having depth bands on the discs, you will get a good stand even if they are planted a bit deeper, but any planting deeper than one inch is wasting a lot of your time and your seed.
(2) Grasses. The prairie grasses you will be most interested in are big bluestem, little bluestem, indiangrass, sideoats grama, and switchgrass. Eastern gamagrass and prairie cordgrass are wetsite species that can best be spread vegetatively, by planting rootstocks, rather than by planting seed, although both do set seed. There are many other grasses that formed a part of the tallgrass and mid-grass prairie communities, but the ones listed above will be the most common dominants in your native stands. Most of the grasses flower in the early fall, taking advantage of the September rains to bear fruit. In dry years, moisture stress will cause them to flower earlier, but in normal rainfall years you can find the prairie grasses in full flower in October, with seed maturing from late October to mid-November. Big and little bluestem turn reddish when mature, and indiangrass and switchgrass turn a gold or yellow at maturity. Just as with the forbs, you start watching the grasses when they shoot up a flowering stalk or culm. Close inspection will reveal that grasses “bloom” much like wildflowers, with recognizable flower parts extruding from the florets. Inspect them carefully as they mature, and you will find that the seeds of grasses also go through the watery stage, the milk stage, the soft dough stage and the hard dough stage. To get good germination, you still need to wait until the majority of seedheads are in the hard dough stage before you start stripping or otherwise harvesting seed. Prairie grasses shatter soon after full seedhead maturity, but not as quickly as most wildflowers, so you usually have several weeks of collecting time on the grasses, barring a severe storm or other shattering event. When the stand is mature, you have a choice of methods of harvesting, storing and planting grasses, depending on the size of your project, the amount of available grass seed, the equipment you have available to you, and the time you have to devote to the task. If you have a small project, perhaps an acre or less, you can hand-strip enough seed from native stands to get yourself a start, particularly if you press into service your friends, spouse and children. Just get some big paper sacks and start stripping the ripe seedheads into the sacks, collecting as much as you can. There will be much more bulk and trash than seed, so don’t be overly impressed with your efforts. Keep on collecting until you have a huge amount, far more than you think you will need. You will then have collected about a tenth of the amount you will need! You will get blisters, etc., but keep on collecting. Seed set is often erratic in native stands, and you need to get lots of bulk for the sake of a few good seeds. If you do not plant it at once, dry it in the sacks, as you did the forbs, or in boxes or shallow trays. If you have a big project, then you will need to harvest seed with either a seed stripper, a combine or by curing seed hay. The method of seed harvest pretty well determines what you do with the seed, how you treat it, and when you plant it. If you cut seed hay, your technique will be as follows:
(a) You will have previously prepared a seedbed by repeated discing and harrowing to kill sprouting weeds, to break up the ground and create a soil mulch.
(b) You will then cut the native grass when a majority of the seedheads are mature, using a sickle-type mower to cut the grass in swaths and lay it gently down. Don’t crimp it, or you will shatter the seeds. Cut it early in the morning when the grass is damp, so that you shatter as little seed as possible.
(c) Then, with a hay rake, such as a side-delivery rake, you windrow the seed hay. It can then be baled, or go to (d).
(d) Or, fork it into a grain trailer as bulk hay, and transport it to the site you are to plant.
(e) Then, pitchfork it out of the moving trailer, towed by a small tractor at a slow rate of speed, covering the field as evenly as you can. Toss the forkfuls of seed into the air to get help from the wind.
(f) Finally, roll, cultipack, harrow or use a brush drag made of tree branches to mix the seed hay with the mulched soil and get the seeds somewhat covered with earth or hay.
This is, of course, all done in the fall, contemporaneous with the harvest. There is no need to dry or store the seed, as you plant it the same day you strip or cut it. Good stands can be obtained in this way if you cut the hay at the right stage and if you get enough of it. You will also get surprising amounts of wildflower seed in the hay, as a bonus. If you use a seed stripper, you are also collecting bulky and trashy seed, with lots of stems, etc. Your technique is just the same as with seed hay, and you follow all the above steps. If you use a combine, such as an ordinary grain combine, you will be getting a mixture of seed and finely chopped chaff. This mixture can be planted by the use of grass drills, commercial or shop made, and this seed should be carefully spread to dry, in a shallow layer, turned regularly, and kept dry until planting time in January or February. It is then drilled into a prepared seedbed, which has been created by repeated discing and harrowing during the winter, and allowed to set out and settle under rainfall. When storing grass seed, it is a good idea to store it in bulk, rather than sacking it up. Rodents are less attracted to bulk grass seed, stored in a trailer for instance, than to sacked grass seed. They seem always to eat holes in the sacks and nest in the seed. We use flatbed grain trailers to dry and store seed, under rainproof sheds. If your combine is properly adjusted, you can usually get clean enough seed to plant without secondary cleaning. However, you can clean your seed without too much difficulty and remove some of the larger stems and leaves, by making a “scalper” of one-fourth inch or one-third inch hardware cloth screen, mounted on a 2’ by 3’ wooden frame. Set this up on sawhorses and scalp the dry seed through it, onto a tarp spread out below the screen, and you can eliminate a lot of trash. This same technique, although more laborious because of the greater amount of trash, can be used to clean grass seed collected with a seed stripper or even to clean small lots of dry seed hay. You can devise motorized, shaking scalpers for larger lots and more complex projects. For planting through an ordinary grass seed drill, you need to have the seed as clean as possible, in order to minimize stopping up of the seed spouts as the seeds drop by gravity down the spouts and into the small furrow opened up by the rolling disc opener. Therefore, if you plan to collect seed by stripping or cutting hay, and then plan to plant it with a drill, you will need to do some secondary cleaning.
Most folks get interested in prairies, decide that it would be fun or a good experience to create a mini-prairie, and plan to use a tract of land, large or small, that is already owned. Although this will work, the ideal method would be to make the decision and then look for and purchase land that is suitable. Although replicated prairies can range in size from that of an urban garden to hundreds of acres, and since even small projects can help educate oneself and foster a greater appreciation of nature and diversity, we are not trying to discourage anyone from attempting any form of prairie replication, any place, any time, or by any method. Neither are we trying to discourage anyone from trying to improve or restore their existing grasslands or pastures, because this sort of effort is also worthwhile and fosters greater appreciation of prairies in general. However, it probably does help if you have an “ideal” tract in mind from the start, if you are serious about prairie replication. So, here’s the “ideal”:
(1) A tract of 50 to 100 acres, or as much more as you can afford. Larger tracts seem to be able to sustain themselves as an ecosystem better than small tracts, although there are many variables involved. A 1,000-acre prairie is a rare beauty!
(2) Level to gently rolling land is best, free from terraces, erosional ditches, streams, woods , fences or treelines.
(3) Fertile soil, suitable for growing crops. Deep soil is best. Very shallow, rocky soil is problematic.
(4) Land that has been in crop production and is generally free from weeds and Johnsongrass or other strong competitors. You need to look at the history and past uses of your proposed tract, as weed seed can lie buried but viable for many years.
(5) Land that does not currently border a pasture or roadside where Bermuda grass (common) grows or where King Ranch Bluestem grows. There is no point in setting up right next to strong competitors. Since most public roadsides are infested with KR Bluestem, you may wish to avoid them to the extent that you can.
(6) Avoid low, very wet, heavy clay soils, if you have any choice. Such soils are subject to invasion by many tough competitors, such as the ragweeds, sump weeds, May sunflower, goldenrods, dewberries and so forth. Higher, better drained soils seem to be best.
(7) Since you may be burning every few years, it is best not to locate right next to a bunch of rural homesites, as the smoke can create neighbor problems with some folks.
By now, you may wonder if there really is any “ideal” site for a prairie replication, in light of all the above requirements. However, the truth is that such lands, generally open farmland, are plentiful, probably cheaper, and readily available not far from most cities. The tracts with creeks, trees and hills are the first to be purchased by urbanites wanting to move to the country, and generally bring the higher prices. If your land is not ideal, then you need to consider making it more ideal before you plant. Take down perimeter fences, doze out tree lines, remove all trees and brush, level all terraces, fill in all gullies, and sculpt the land so that you can safely and easily disc and shred it during your project. Fences attract birds, who sow weed and tree seeds. Fences shelter brush, saplings and poison ivy. Fences are impossible to shred under. Trees not only spread their own seed by wind and water, but attract birds, who carry the seeds further into your prairie. We certainly do not say that you cannot have a prairie in the middle of the woods, with a pretty creek nearby, and woods as a wildlife haven, but you will be planting your prairie in the very midst of the enemy camp and will have to work much harder and forever in a battle to preserve it. We did not know or think about the foregoing when we first started our prairies. We have learned these lessons the hard way, by making mistakes. It has been a constant battle against woody and weedy invasion, because we built our prairies right beside creeks, fence lines and woods, and because we did not doze down all terraces and shape all gullies before planting. We’ve learned a lot since 1969, much of it by trial and error, mostly error! Almost everyone wants to fence their property. It seems to be one of the attributes of ownership, and important to most folks to establish their property lines and territory. However, you rarely have any trespassers on prairies, and there is generally nothing to steal on a prairie, so fences really are not required. Fences also encourage owners to “make some use” of their prairie by grazing, most commonly by a few head of cattle, a horse or two, and Heaven Forbid, goats, miniature Zebu cattle, midget donkeys, or sheep. While a really good manager can graze a prairie without harming it, good managers are hard to find, and the skills are not easily learned. You will probably go backwards on your prairie project if you plan to manage your prairie by grazing, most likely by hitting it too hard at the wrong time or for too long a period. Unless you have ample other tame pasturage for your stock, so that you can turn them into the prairie at the proper time, remove them at the proper time, and not feel compelled to hit the prairie a bit harder because you have run out of other grazing, you will do best to forget replicating a prairie. Is prairie replication only for the wealthy? What about the person who has limited means and must make some return from a tract of land in order to justify its purchase? What about the person who has inherited an undivided interest in a family tract, sharing ownership with siblings who have no interest in creating a prairie? These are genuine problems. Ideally, the prairie ownership should be segregated, so that only one owner is involved. Also, the fact should be faced at the outset that not a lot of money can be made off a prairie. You can cut one cutting or possibly two a year and sell the hay, if a market exists, or use it on other pastures you own or control. If you are very good at prairie and grassland management, you can graze a prairie for short periods during the year, and get some return from the gain of your animals. But you are unlikely to net as much income from a prairie as you could gain from renting the same land to a farmer for crop production, although you will get a poor return either way. Prairies do not generally pay their way, and the creation of one and the management of one is a labor of love. You are creating a rare and wonderful thing that pays you by its beauty and diversity. We do not regret any of the sums we spent on our prairies, nor the years of hard work, nor the time involved, and would not sell an acre of them for any sum. A partial species list for Central Texas is shown above at Appendix One. This is not an exhaustive list. It is difficult to locate, identify and collect seeds or rootings from many of the less common or less visible prairie plants, and it will take you many years to find some of them at just the right moment. However, this list does give you some ideas to toss around, and covers a majority of the more common prairie species for Central Texas. However, we collected and planted Maximillian sunflower in all our prairies. Having observed it since 1969, we would not advise planting it in any prairie on the blacklands. It is too aggressive, spreads by tillers and underground shoots, and will overpower and force out many other prairie grasses and forbs. It will come in all on its own, but keep an eye on it, and use Roundup spray or wick treatments regularly to control the size and spread of the plants that establish themselves in your prairie. If you strip or combine your seed from existing stands, you will get plenty of it without planting seeds all over! Likewise, although goldenrod is frequently found in low, moist prairies, it is best to avoid planting it and to also keep it from spreading too much. A little bit goes a long, long way!
These devices range from expensive ($5,000 to $10,000) grass drills, with double disc furrow openers, to shopmade planters with cotton planter boxes, to the old-type pelletized fertilizer spreaders. Under certain conditions, any of these devices can give a good stand.
(a) Grass drills. There are several manufacturers of double-disc pasture and range seed drills. These usually have a row of boxes for chaffy grass seeds, and a row of smaller boxes for small, clean seed. Implement dealers or your NRCS range conservationists can give you addresses. Some soil conservation districts have these machines for rent to cooperators, and you can probably find one in your area by inquiry with the local soil conservation work unit.
(b) Fertilizer spreaders. The old-style fertilizer spreader, with the long box and an agitator in the bottom, putting out fertilizer in a broad swath at right angles to the tractor’s long axis, is useful in planting trashy seed. One brand that we have used is the “Ezeeflow” or something like that. The seed is spread on the ground by the spreader, and then you roll it with a cultipacker to press it into the ground, or harrow it lightly with a toothed harrow, or drag it with a brush drag. Some sort of following treatment is needed behind the fertilizer spreader, to cover the seed lightly.
(c) The shopmade planter. For about $1,000 a handyman with access to a welder can build a great homemade seed drill. Use a two-row cotton planter, with cotton plates, and rig it on a triangular pipe frame to run on two automobile tires that roll directly over the freshly planted seed as packer wheels. Instead of the usual plow for a furrow opener, adapt two double disc openers from a grain drill. The whole rig tows behind the tractor like a little trailer, and the cotton planter boxes will plant any kind of dirty seed, no matter how much trash is in it. We can give you a sketch or photo to guide you in the building of your own.
(d) The pitchfork. As indicated above with seed hay and stripped seed, you can get good stands by just forking the seed and hay out onto prepared ground, and then dragging a harrow or homemade brush drag over it to lightly cover the seeds.
Native grasses and forbs are hardy plants, designed by nature to colonize and spread. Thus, it is not absolutely essential to plant them upon a prepared seedbed unless your project is partially financed by the government, which requires seedbed preparation and fertilization. We have had slow but sure success by planting into stubble from a prior crop, by planting into dormant Johnson grass, by burning and planting into the burnt stubble, and by simply forking seed or seed hay out onto whatever was growing there at the time. However, there is no doubt that the quickest and most reliable way to get a stand is to plant into a clean, firm seedbed. Normally, such a seedbed is prepared by chiseling the area, discing it, and then allowing rain to fall on it to firm it up and break down clods before planting. Do this in the winter, not long before you intend to plant, because annual weeds will soon sprout if you prepare your seedbed too early. An alternative would be to prepare the seedbed early, let the annuals sprout, then hit them with Roundup or a very shallow discing several weeks before you intend to plant. Roundup should not be used immediately before planting or during planting, for fear of damage to the grass and forb seedlings. An ideal seedbed is clean and free of weed growth, free of large clods and relatively level. If there are old terraces on the plot, it is best to plow them down or flatten them with a bulldozer or road maintainer before preparing the seedbed, as you will always have trouble with weedy growth in the dips behind the terraces and on the tops of the terraces. The firmer the seedbed, the better, as ultra-loose soil causes seeds to be buried too deeply, and also tends to insulate the seed from the moisture below it, delaying germination. Plan to plant early, like in January or February. The quicker you can get your seedlings off and growing, the stronger they will be when Johnson grass comes on in April and May, and the better use they will make of good moisture and moderate spring temperatures.
In selecting your seed, try to get seed of the same species from as many different remnants in your area as you can find. There is substantial genetic variability among, for example, big bluestem plants from meadows a few miles apart. Because all these prairie remnants are threatened with destruction, and because we need to preserve as much variety as possible in the gene pool of each species, you will be helping the plants and helping your prairie by gathering seed from many nearby sources, rather than from a single source. Someday, your replicated prairie may be the only remaining example of the genetic variability and adaptability originally found all over your part of the state. Try to avoid commercial seed sources, unless you check them out well and unless you know the geographic origin of your seed. You can go into any feed store and buy prairie grass seed, but it may come from the Texas panhandle or even from Oklahoma. Because of many factors, including temperature, photoperiod, etc., prairie plants do not do well when moved a long distance from their point of origin. Try to always use local seed sources. A good rule of thumb is that prairie seeds should not be planted more than about 100 miles north or sound nor more than about 75 miles east or west of their point of origin. Big bluestem from the coastal prairie or the panhandle is just not the same as big bluestem from Central Texas, even though the species name is the same, and the plants look very much the same. Always know where your seed comes from! Some varieties have been released for geographic areas, such as Central Texas.
Native plants are hardy. They can handle most weedy competition and dry weather if given a small amount of help. The best help you can give them is to mow to a height of between six and eight inches about four or five times during the first two growing seasons. This will knock down the competition from Johnson grass and annual weeds, will cut down the competition for moisture, and reduce shading by taller weeds and grasses. Because you will be wanting to mow during the first two years, you probably will want to plant only perennials at first, adding in your annual wildflowers by overplanting after the perennials have become well established. You would necessarily wipe out most of your annuals in the first two years of mowing. However, most of the better prairie plants are perennials, so you are going to have a nice variety even with mowing. Annuals such as basketflower, an important prairie forb, will fit right in later on without difficulty. Avoid grazing and burning for the first two years. Let the native plants get well established before they are subjected to this type of stress. If you do intend to graze your prairie, remember that continued close grazing during the growing season will eventually wipe out your tall grasses and forbs unless you give your prairie regular rest periods during the main growing season. It takes good management to maintain a small prairie by grazing livestock. Goats, sheep and equines are anathema to prairies. Don’t be surprised if your plants are very small and your prairie appears to be a failure at the end of the first year. Prairie plants grow down for the first year, and are very cautious about putting up lots of top growth until they have deep roots to sustain them. You will see much more growth upward the second year, and after that, your prairie can hopefully take care of itself against all competition, with a bit of TLC.
We do not advise the use of herbicides in seedbed preparation, with the sole exception of Roundup applied to winter weeds several weeks before planting. Most herbicides have residual effects that may last more than one growing season, and may retard the germination or early growth of prairie plants. Herbicides, used very carefully and applied by spot sprayer or hand wick, can be used to control weedy or woody invaders in a prairie, but almost always some damage or kill of desirable plants is experienced. Broadcast spraying herbicides can really do harm to your prairie, so use herbicides with great care, usually by spot spray or wick application only.
Once you have a prairie growing and doing well, it requires some management to keep it from being invaded or damaged. Birds and the wind usually bring in elm, hackberry, snowberry, and poison ivy. Cattle usually bring in mesquite. These and all other woody invaders must be controlled. It is better to seek them out and control them while they are few, young and small. Temporary control can be gained by hand-clipping with pruning shears. Do this every year, in late spring or early summer, when the woody growth is not obscured by the taller grasses. Shredding or haying will also retard the growth of woody invaders, but it does not totally eliminate them. Burning the prairie every two or three years will usually kill the smaller saplings, but burning too frequently or at the wrong season can be harmful to the prairie. Poison ivy usually requires the use of a spot spraying or a handwick and Roundup, to kill it by wiping the herbicide on the leaves. You will always kill a few non-target plants also, so be careful. Johnson grass is a tough invader. It can be retarded by mowing at first, but occasionally you must hit it with a wick (hand or tractor mounted) and Roundup. It is usually growing above the prairie grasses in late spring and early summer, and can be hit with the wick without doing much damage to the prairie plants, if you are very careful! Grazing on a continuous basis is fatal to prairies. That is why you do not see the better prairie plants in fenced cow lots in the Blackland Prairie. Continuous heavy grazing under fence will give you a pasture of common Bermuda, buffalo grass and broomweed, if continued for any length of time. We prefer to graze prairie plantings lightly, in the dormant season (October through March), and to watch the impact pretty closely. Light spring grazing is also o.k., but only on an every-other-year basis. Horses normally do more damage than cattle, and sheep and goats are notorious for their damage to prairie plantings. In general, you should regard grazing as a means of management, rather than an end in itself, and grazing should be stopped if damage is ensuing. The tracking of livestock in a wet prairie will nearly always encourage the growth of weedy species in the tracks, and the manure patties are ideal germinating spots for other weeds. Mowing is a good way to control annual weeds that are getting out of control. Let them grow through May, or early June, but not to the point of flowering or setting seed, and then mow them back. Many will not regenerate, but some will, depending on the rainfall and temperature and the state of maturity at the time of mowing. By mowing, however, you may harm some of the prairie annuals, so watch them and try to mow after the better ones have matured their seed. Do not “scalp” the prairie! Mow no lower than about 6” off the ground. Try to keep tractors and mowers out of wet, soggy prairies, because their weight tends to compact the soil too much. Haying each year is common in prairies. Continued haying will eventually alter species composition in some degree, but normally it is an accepted tool in prairie management. It does help keep down woody and weedy growth, and tends to favor the grasses above the forbs. Cutting more than one crop of hay per year is not a good practice. Cut hay early, no later than the first week of July. This leaves time for the plants to grow and build up their necessary food reserves for setting seed, for winter and the following year. Hay bales should not be allowed to sit in the prairie, but should be moved at once. A bale, or even a broken bale, if left in one spot for a week or so, will kill the prairie plants under it. Round bales should be removed from the prairie plot for storage. Stacking bales or storing round bales on prairie sod will kill the prairie plants under the haystack and result in weedy invasion. Haying involves the use of tractors, mowers, trucks and trailers in the prairie. Avoid the impact of heavy equipment as much as you can, as prairie soil is relatively loose and aerated and can be compacted easily. Controlled burning is a valuable management tool. It helps remove accumulated duff, renews the vigor of the prairie plants, kills small woody saplings and helps favor the grasses as against aggressive invaders like goldenrod. However, burning at the wrong season or too often can harm the prairie. We try to burn in December through February, at a time when there is adequate soil moisture to protect the roots and crown of the plants. Burning later hurts many of the early plants. Summer burns, during drought conditions, can do permanent harm to the prairie plants, although it may give a better kill on woody brush species. The techniques of controlled burns are beyond the scope of this discussion. Call us if you need advice. In general, we mow a firebreak around the prairie, usually about 40’ wide, and then mow the prairie up into blocks, with mowed strips between them, giving you a better chance to maintain control. We usually start at a downwind edge, usually a corner, with firebreaks going down each side from the corner, and burn with a backfire, against the wind, under strict control by fire flappers, sprayers, and backpack sprayers, until a safe perimeter strip is burned. If you start your backfire in the mowed strip, it will not be as likely to get away from you. Once the firebreak is burned all across the downwind area and up the sides, then you can start setting narrow strips of downwind fires to burn down to the firebreak. Use narrow strips at first, as prairie fires can jump long distances with a strong wind. Use common sense. Advise your neighbors of the burn, call the local fire department to advise them of a controlled burn, comply with any state or local burning ordinances, and try to avoid burning on excessively windy days. Have enough manpower on hand to control the fire and provide support. Wear a mask and protective clothing, and avoid getting trapped or having your pets or equipment trapped by the prairie fire. Burning a prairie annually is not required, and may be harmful. We try to burn at intervals of 2 to 3 years. To maintain the bird, reptile and small mammal population, you can burn only part of your prairie in any one year.
All of nature is dynamic, and change is the order of the day. There is no really “stable” ecosystem if you look closely enough. In all of them you will find species changes over time, as one species out-competes another for a niche, or as climatic variables such as drought, flood, temperature, etc. manifest themselves. Prairie plants are generally hardy, deep-rooted, tolerant to drought, heat and cold, and can reproduce and maintain themselves over the years, but only under “natural” conditions. Natural conditions of the prairies included regular wildfires that swept across them, sometimes annually, or at longer intervals, set by lightning strikes or by the hands of early humans. Wildfires helped maintain the prairies from takeover by their ultimate enemy, woody plants. Frequent fires favor the grasses and forbs of the prairies, to the detriment of woody invaders like trees and shrubs. However, for the past 150 years or more, fire has been treated as an enemy and has been avoided, suppressed or controlled everywhere. Thus, woody invaders have surrounded our prairies and are ever encroach¬ing from all sides. Whereas, in earlier times, wildfires would burn, sometimes for days, over miles of prairie, burning hundreds of thousands of acres, killing or setting back all woody species, until ultimately stopped by a belt of woods , a big creek or a river bottom, now most prairie remnants are not burned at all, and woody invaders have no natural checks to operate on them. So, we must help prairies maintain themselves, by a constant battle against woody and weedy invaders. Weedy invaders, many of them foreign to North America but now fully naturalized and at home here, are also a threat to your prairie project. We must help the prairies by fighting weeds as well as woody species. Remember, in the absence of regular fires, the natural progression of plant succession is from grassland to woodland, and your prairie will become a woods unless you regularly fight to maintain it. Cutting hay yearly, or mowing at least yearly, will set back woody saplings and retard their efforts to spread, but they are very persistent and will continue to live and grow even very close to the ground. Fire will kill some species, and severely set back all woody species, so regular burnings are the best treatment method. However, around the edges, gullies, fences and rough spots, mowing and shredding will not reach the woody saplings. Many, such as wild plum, not only reproduce by seed but by underground sprouts, so that dense, ever-spreading thickets form. Poison ivy, one of the toughest woody invaders, spreads by both seeds (carried by birds, who consume the waxy coatings on the fruit) and by long-reaching underground stems, making a dense, ever-spreading clump. Goldenrod, KR Bluestem, Max Sunflower, and many others spread and clone out the same way, gradually increasing their circles of dominance year by year, unless you kill them regularly. During the first year of prairie plantings one of the worst competitors is Texas croton, dense and low-growing. So, what steps can you take to keep your prairie from being adversely affected by weedy and woody invaders?
(1) From the start, plan your prairie to discourage such pests. Avoid fencing, trees, woods, gullies or rough, rocky spots that harbor invaders and give them refuge from fire or shredder. Before your first planting, disc the soil several times, after giving weed seeds a chance to sprout.
(2) Inspect your prairie regularly, on foot or by ATV, looking for the very first evidence of weedy species or young trees, vines or woody pests. Kill them then and there, by digging them up, treating them with diesel fuel, spraying or wiping with Roundup herbicide, or spot-spraying with a herbicide-water mix containing Grazon P+D, Remedy or Surmount. If you inspect regularly, spot-kill the invaders regularly, you use only very tiny amounts of herbicide and do no general harm to the prairie plants. Herbicides can kill or burn prairie plants, but if you are inspecting regularly and acting while the invaders are young and vulnerable, your spraying will never adversely affect the prairie planting as a whole.
(3) Never let a year go by without inspection, spot-killing, shredding or burning, or a combination thereof. In one year some saplings can spread and put down an extensive root system, and be much harder to kill the second or third year.
(4) Remember the value of inspection and knowing your plants. By inspecting and “working” your prairie yearly, or more frequently, you will soon know all the plants at various stages of growth and become a much better practical naturalist.
(5) Do not be afraid of herbicides. Broadcast spraying can ruin a prairie, but spot-spraying is required to save it from woody and weedy invaders. Use them according to the label. Some require a permit and education. However, at the low levels of use you will engage in, you can usually buy them at a lawn and garden center in small quantities and have no problems. Study them and their labels carefully. Avoid contamination of clothing, eyes, skin, equipment, or the environment. Most are not suitable for use in wetlands or near watercourses or ponds. Never spot-spray on a day with strong winds, as minute droplets can be carried by the wind to non-target plants. Use a coarse spray, not a fine mist, as this reduces drift.
(6) On very aggressive plants like Max sunflower, goldenrod, poison ivy, dewberry, mustang grape, and others that sprawl out or spread vegetatively, you need to spray them around the edges every year, to retard their clumps. Keep them under a maximum diameter of three feet, or they will soon get out of hand. Poison Ivy, dewberry, wild plum, goldenrod, rough-leaf dogwood, sumac, mustang grape and other very aggressive plants should be totally eradicated each year.
(7) If you are stuck with fences, gullies, treelines and other places or structures that harbor invaders, you must patrol these areas with a spot sprayer at least annually, with Roundup in the sprayer, knocking back all the invaders. If you do not do this, you will eventually find the edges moving out into your prairie year by year, like a pursestring draws together the top of a bag.
(8) Burn at regular intervals, if at all possible. If you cannot burn, then shred annually, and supplement by spraying the invaders you cannot reach with a shredder.
(9) Eventually, there is an end to spraying. As your prairie becomes a dense growth and fully mature, seedlings have a hard time establishing themselves, and burning will almost totally control the invading species. Fence and tree lines are never safe to ignore, but your activities along the edges will be limited, if you fight hard the first few years to prevent invasion and then shred and burn regularly.
(10) On burning, we prefer to burn between December and February. A March burn will work o.k. sometimes, but some plants are already greening up by then. Burning in the summer is sometimes done on rangelands, or on very large natural prairies, but we tend to favor burning in the season of dormancy of a majority of the prairie plants. Opinions differ as to when it is best to burn, but we’ve been burning since 1969 and have a pretty good record in the Blackland Prairie for both successful burns and safe ones. Burning every other year is not too frequent, but many burn only every third year. You can alternate blocks of land and burn something every year if you desire, and leaving some unburned blocks each year will keep your small animal and bird populations healthy. However, we frequently “let it all burn” and have found that the small animals and birds are well-adapted to burns and to survival in the face of a prairie fire.
This is not intended as a textbook for burning prairies or ranges. Large-scale rangeland burns in open country with lots of grass and duff on adjoining lands is technical and demanding. Many factors must be considered in such large burns, usually done for the control of brush and mesquite, so that you do not unintentionally burn adjoining lands of yourself or a neighbor. In the ranch country, a wildfire, with a strong wind behind it, can move across country 15 to 30 miles per hour and can burn for many miles before being brought under control. On the other hand, Blackland Prairie tracts are normally small, frequently surrounded by plowed ground, and pose a much lower risk of wildfire when doing a controlled burn. The need to burn regularly is why we suggest that you plan your prairie from the outset with a view to safe burns, avoiding high-risk environments. One way to do this is to allow from the outset for a regularly-disced firebreak or perimeter strip all around your prairie planting. A plowed firebreak 20 feet wide, when coupled with a shredded strip of the same width prepared just before the burn, will allow you to backfire and burn with safety under almost any conditions. Advance planning, even when first planning your prairie planting, can make regular burns a fun and exciting, low-risk experience.
Points to consider when planning to burn a prairie:
(1) Never set a fire until you are totally ready, have planned your burn, have instituted proper safety precautions, are prepared to self-rescue if something goes amiss, have all your equipment and personnel ready, and have given any required notices and courtesy calls to Fire Departments, Fire Marshals, and neighbors.
(2) Safety of yourself, burn personnel, family, livestock and pets is mandatory. Remove all livestock from the burn area or downwind of the burn area. Pen or chain your pets. Dogs have a bad habit of chasing fleeing rats and mice into grass in front of the flames, and their natural instincts for survival are modified by domestica¬tion, so that they will let the fire roll up on them. Never forget that the amount of radiant heat put out by a prairie fire is unbelievable, and reaches far out in front of or behind the flamefront. Air currents are generated by such fires, and can bring a blast of withering heat upon you without warning. Never try to jump across a prairie fire. Children love fires, but they should never be allowed unattended near a prairie fire. The speed of the flamefront can be deceptive, and it can catch a running person or trap the person in a low spot or enclave. Once the firing starts, all personnel must stay behind (upwind) of the burning grass. Do all your backfiring early, before you ever allow a flamefront to roll with the wind, and be sure all personnel are warned and in safe places before you set the fire to run with the wind. Avoid wearing anything but 100% cotton clothing, and wear particulate masks to help keep soot out of your lungs. By proper planning and appropriate safety considerations you can avoid anyone having to over-exert themselves. Fighting a fire that is out of control is hard, hot work and has brought on heart attacks, even fatal ones.
(3) Notices to others are important, so you need to think about them in advance. Every county has a number to call to report your intention to do a controlled burn. Call that number and give the details and location that the taped message requests. It is also wise to call the County Fire Marshal and advise him of the time, place and date of your controlled burn. Sometimes a “burn ban” is in effect in a county, and these must be respected. If you have a very safe and protected burn, you may be able to request an exception. Neighbors, especially those downwind, should be called the day previous, to advise them that a controlled burn will be done, that smoke and flame will be visible, and that some odor or smoke may drift their way. Advise them that you have your cell phone at all times and are prepared to call the Fire Department if needed. What you desire to avoid is anyone calling the Fire Department, thinking that the fire is accidental. Next, all prairie fires create white smoke that will rise and be visible for miles, and VFD’s from nearby towns may come without being called. Calling them in advance and letting them know you do not wish their attendance is one way of avoiding the sudden and nuisance arrival of a bunch of fire trucks and eager volunteers! Smoke and fire bring the curious, so expect to see many cars on the road, bearing people who have seen the smoke and are curious. If personnel numbers permit, station someone down at the gate or entry road to turn back the curious, as you do not wish to have them driving into the area to be burned. In our many years of burning I’ve had jeeps, ATV’s , firetrucks, 4X4’s, motorcycles, and people on foot trespass on the property in an effort to see what is going on, some in a misguided effort to be helpful. Keeping them away can be a real help. If you plan properly and have the right equipment and adequate personnel, you should not need the VFD at all. However, if you do need them, it is wise to have their number on your person or in your cell phone. This is groundwork you lay in advance with the local VFD’s.
(4) Equipment for burning is simple and not expensive. During the backfiring you will do to prevent the escape of your fire, you will need a few simple tools, available by mail from a forestry supplier. These include several “fire flappers”, a couple of Indian backpack sprayers (made of soft PVC material and holding about 5 gallons of water), and a couple of propane torches for setting the fires. Keep clean water handy to re-fill sprayers. You will need several bottles of propane fuel as well. Good old “strike anywhere” kitchen matches work well. You can also carry a welder’s spark lighter or a butane lighter for lighting your propane torch. “Drip torches”, used in many professional burns of forest and range lands are, to our way of thinking, expensive and not a bit better than a handy propane torch off your work bench, and we’ve burned a lot of prairie with just kitchen matches struck and dropped as we walk. Fire flappers, a hoe handle with a piece of wide rubber belting at the end, are the best tool you can find for fighting grass fires along your backfire route or anywhere that the grass is not overly tall. The air blast from a flapper just blows the flames out. Get the commercial varieties from someplace like Forestry Suppliers. The Indian soft PVC backpack sprayers have a trombone pump that lets you apply a stream or spray at your selection and five gallons of water are not too hard to carry on the back with the shoulder straps provided. These are good tools, and treated correctly will last for years. For a woman’s use, put only three gallons in the bag. Finally, if you have a small tractor, it is wise to also get a pull-behind tank with a PTO sprayer and a hose and wand, allowing you to spray small fires from the tractor seat. We rarely use more than about 150 gallons anytime in doing a burn, so a 200-gallon tank and pump to match is more than adequate. The smaller, 12-volt electric pumps do not put out enough volume and are not powerful enough for burning prairies, so a good PTO pump, run off the tractor’s PTO, is required and more reliable. Get a good quality spray wand that allows you to shoot a strong, long stream of water. If you do things right, you will not be “fighting” a fire, but will use the spray rig mainly in the backfire phase, or around wooden fence posts, power line poles or other places to be protected from the grass fire.
(5) Remember to think ahead. If you have an electric distribution line on your property, it will have wooden poles, which can be set afire and smolder a long time before the creosote melts and starts burning up the pole. These are expensive to replace! So, in the course of planning your burn, take a shredder or power mower and mow a big circle, say 20 feet in diameter, around each powerline pole, mowing right to the ground. Then, rake the cut grass back radially around the pole, so that there is nothing left to burn near the base of the pole. At the time of backfiring, on the day of the burn, you can either spray around the base of each pole with plenty of water or set a small, controlled fire yourself, and stand there until all the dry grass is burned away from the base of each pole. Having a fire flapper and a backpack water sprayer makes this easy and safe, since you previously mowed around each pole.
(6) Suppose that there is a pipeline across your tract. Be sure and check for any leaks before you burn. Areas of dead vegetation can be a sign of a pipeline leak, along with odors from natural gas or oil. Try to mow around and protect the usual pipeline warning signs and the locations of cathodic protection units that are found along such buried lines. Any above ground pipeline structures should be protected from the prairie fire by mowing and raking.
(7) If you have fences, yours or a neighbor’s, around or alongside the burn, remember that the fire can ruin the anti-rust coating on fence wire and can burn right through wooden posts. Protect the fences by whatever means is available, usually consisting of shredding alongside the fence well in advance of the burn, so that the shredded plants have time to pack down and rot, and so that winter-growing, cool season plants start greening up, forming a non-burning or slow-burning firebreak. At the time of the burn, doing a slow and very controlled backfire along the fence, with tractor sprayer and backpack sprayers handy, will avoid expensive fence damage. Where we have a problem area, such as a fence, or a valuable tree area (pecans, for example) we just regularly keep a strip mowed, all year around, to protect that area and maintain a very short height of growth. This avoids the intense heat of a tallgrass burn, and makes it safe and easy to control any fire that moves toward the protected area on the day of the burn.
(8) A hypothetical burn. Attached hereto is a sheet that shows a typical prairie, with the north end indicated and the normal wind direction indicated. Strips to be plowed, mowed and/or burned for safety are shown. Notes are included to explain what the drawing shows. For different wind directions, just flip the map over and reverse everything. Once you have at least two sides and the downwind corner protected by plowing, shredding and/or backfiring, you can then start setting “strip fires” that burn with the wind and run in the direction of your firebreaks. Once you have at least 100 yards of strips burned, in addition to the original width of your firebreaks, you can go all the way to the upwind end of the prairie and burn with the wind, for the real thrill of seeing a rolling flame front and a prairie fire like the early settlers wrote about.
(9) Wind, speed and direction. Winds that are very strong and gusty are contraindications to a burn, unless you have 100% sure safety downwind. But, light and variable winds can be a problem also, as they can suddenly shift on you and cause the fire to burn in an unplanned direction. Therefore, always listen to the nearterm and longterm weather forecast and check the forecast on the very day of the burn. If a front is coming, heralding a sudden change of wind direction or speed, be extra careful and postpone the burn, unless you actually have 100%, protection in every direction, such as being surrounded by plowed ground or a major stream. We have safely burned on winds in excess of 20 mph, but only when we had previously prepared very wide breaks in every direction of risk, and had plowed ground all the rest of the way around. A steady breeze, not expected to change, of perhaps 5 to 12 mph, is pretty good burning wind. But, never forget that nature is fickle, and that on a local or even regional basis surface winds can change in a moment. Therefore, never trust the wind as a part of your safety planning. Expect it to change, and plan to handle that problem when it comes up. For example, consider the map. If you have two good firebreaks down two legs, and have 100% protection in the downwind direction, and you start strip firing, what happens if the wind reverses itself? The strip fire you just set downwind will roll back on all the unburned grass, including where you are standing, will race back to the south (in the former upwind direction), and will burn until it runs out of fuel or hits a break too big to jump! All your personnel and equipment can be endangered, as well as improvements on the property, or your neighbor’s property. So, you must plan in advance and prepare for the unexpected. A large, wide shredded area upwind, will drop the flame front and help you control a runaway in the event of a total reversal of the wind’s direction. A road, a plowed strip, green growth, a stream, woods without burnable undergrowth, all can serve as a backup firebreak in the event that the wind does a 180 on you. Always keep your personnel and equipment near a safe spot and not out in the middle of a wide expanse of tall grass, in case the wind suddenly shifts.
(10) Burned ground is safe. It can be walked or driven over within a few minutes after the flames have passed, and except for trunks and limbs of woody plants that may lie smoldering for hours, you are unlikely to be burned on recently burnt ground. Just give it a little time to cool down. Movement over burned ground will result in clouds of soot and carbon, so keep your vehicle closed up and keep your mask on. You will look a mess and will have rings of soot around your eyes and in every crevice! Burning is not clean work! If you drive an ATV into burned ground, check your air filter regularly.
(11) Humidity must be considered in planning a burn. Early in the morning humidity is generally higher. During the middle of the day and early in the afternoon it is frequently much lower. Late in the evening, the humidity often rises. Low humidity increases the rate of burning of any grass fire, and high humidity generally retards it. Bottomlands burn more slowly than uplands, in general, due to higher humidity in the lowlands, particularly near creeks and wetlands. A day with very low humidity and very high winds is a day of danger for the person planning to burn a prairie. Under such conditions, be very, very certain of your safety planning, equipment, personnel and methods. On such days even very wide firebreaks can be jumped. A swirling “firestorm” can be creat¬ed, with strong updrafts that carry hot or glowing materials high up into the air, where they may fall on unburned grass before they cool down. Even surface winds, near the ground, can whisk burning pieces of grass out ahead of the flame front, causing fires to break out downwind and in advance of the flame front. Such materials can ignite dry materials and cause an unintended extension of your burn. Beware of brisk winds and very low humidity.
(12) What if the fire gets away from you? The basic rule is “call for help and stay out of the way of the fire”. You can suffer death or injury in getting out in front of a fire that is out of control. It’s best to let mechanized fire trucks handle such a fire. If you plan and execute with care, you will almost never have one get away from you, but nobody is totally immune to error or to bad luck. Don’t kill yourself or your family or friends, get on the cell phone and call the local VFD. If you have talked with them in advance, and kept the number for the call, they will be glad to come. The volunteers always enjoy a good grass fire, and they enjoy teasing you about your “controlled burn” that got away! Always donate each year to the local VFD, generously! Never be too proud to ask for help when you really need it.
(13) Forethought, once more, will save you more often than anything else. If you plan to burn just a portion of your prairie, it never hurts to shred a very wide strip all around the area to be burned, and a much wider strip in the direction of greatest danger should the fire get away from you. Shredded grass is much easier t