Do you have an area of your lawn where personnel are constantly walking? Maybe not just personnel, but you also have equipment going through that area all the time? Are there all sorts of personnel walking in the same areas…personnel coming in and out of the house, in and out of automobiles, delivery personnel or postal personnel? Does your mower or other equipment have to go a certain route on your turfgrass every time? This is what I call a “high traffic” area.
For example, at the gate to my backyard, there is an area that has a difficult time growing turf. Any person or piece of equipment (mostly my lawn tractor) that has to go in to or out of my backyard has to pass through that gate. That turf is always beaten down. And, it looks even worse in the summer, especially during times of drought stress or heat stress. And, that area happens to be under a great deal of shade. So, I’m out of luck on many counts.
When your turf is being trampled, there are basically two things going on. First, there is direct, physical damage being done to the turf plants. Second, the turf may suffer the consequences of soil compaction. The kinetic effects on the turf leaves are self explanatory. The soil compaction may not be so self explanatory. Compacted soil hinders root growth, water penetration and the take up of necessary nutrients. Compaction occurs when soil particles are pressed together. That pressing together of the soil particles eliminates the pore spaces in the soil that are required for air and water. As many of us know, soils high in clay content are more susceptible to compaction than soils higher in sand or silt.
What causes soil compaction? In agriculture, it is usually rain, improper tillage, minimal crop rotation and wheel traffic. Those all contribute to compacted soil on the farm. In your yard, it is usually foot or wheel traffic. Real hardcore pedologists (Like me!) use the term “bulk density”…the bulk density of soil. Bulk density is a measure of a soil’s mass per unit volume of soil. It is used as a measure of soil wetness, volumetric water content, and porosity. Factors that influence the measurement include organic matter content, the porosity of the soil, and the soil structure. A soil that has a well developed structure will become less dense as porosity increases; as a result the bulk density of the soil will decrease. Soils which show massive structures and less porosity will show higher bulk densities. This blog post will go full circle. More on soil density later.
As I’ve said several times throughout this blog, species selection should be the first consideration if you want to take on this problem. Different types of turfs vary in their ability to tolerate wear. Now, I’m here to tell you, if an area has real excessive (and I mean a whole lot) of foot and/or wheel traffic, no turf is going to stand up to it. What is real excessive? Well, I’d say that would be constant movement over an area. Not a turf on this planet can handle huge amounts of traffic.
Yet, if there is a moderate amount of traffic, there are some species that are better than others. The most tolerant warm season grasses are zoysiagrass and bermudagrass. Of the cool season grasses, perennial ryegrass and tall fescue are pretty tough. Kentucky bluegrass is fairly tough but rough bluegrass and colonial bentgrass are terrible.
Here’s a quick, final thought on species selection. My lawn is primarily tall fescue. In fact, you could call my lawn a “cool season blend”. Remember – a mix is comprised of more than one species of turfgrass; a blend is when there is more than one cultivar within a species. One of my goals for my lawn is consistency. I would not want to plant, say, zoysia in that area on each side of my backyard gate. It would look different. It would ruin my lawn’s consistency, and possibly spread. So, planting a patch of a different species in that area is not really desirable for me.
There are some management practices one can do to enhance your turf’s tolerance to traffic. One thing I say all the time – for many reasons, now this one - mow your turf high. We know that longer turf leaves have more leaf surface exposed to the process of photosynthesis. And, mowing higher encourages deeper roots. Also, mowing is always a stress. Perhaps mowing that area less goes hand in hand with allowing the grass to be longer and will help it deal with traffic better.
Small amounts of thatch are acceptable. If you read my blog post titled “Thatch”, you know I have said you should not have more than half an inch of thatch. That still holds true. But, having a small (less than 0.5 inch) layer of thatch can provide a cushioning barrier. It keeps the turf leaves from actually getting crushed.
From a fertilizer perspective, another thought is to reduce your nitrogen application. An excessively thick and lush stand of turf is more susceptible to damage. Increasing your potassium application will also increase the wear tolerance of your turfgrass.
The only way to alleviate soil compaction is to core aerate. Like many golf courses, core aerating more than once a year is an excellent thing to do, even if you don’t have compacted soil. Those compacted cores are removed and replaced with holes that allow greater air and water movement. Turfgrass roots grow into those holes and are exposed to air, nutrients and water. If I could, I’d aerate my lawn at least twice a year – once in the fall and again in the spring. Although most compaction is found in the top two inches of the soil, the deeper the cores, the better the results. Read my blog post on “Aeration”.
Finally, some (other) experts say a light topdressing of sand after the aeration will change the soil texture. I’m not a big fan of that. Why? Because most homeowners don’t do that correctly. Golf course superintendents get it right…most of the time. It must be a VERY LIGHT topdressing. And it should only be done in certain circumstances and in certain locations. Messing up your soil texture is very difficult and very expensive to reverse. As I said in my “Establishment” blog post, just putting down 1 to 2 inches of sand can cause “layering” of the soil. When soils have these layers, the layers can become impermeable. When you have impermeable layers in your soil, that is another different set of problems. Having compacted soil pales in comparison to the problems posed by layered soil. If you have layered soil, might as well rent that bulldozer with the huge soil ripper attached to it. You want to add something to your soil after aeration? Add organic matter like humus, peat or other soil conditioners or soil amendments like that.
While I’m thinking about it; let me say this. Gypsum will not break up compacted soil. It will increase the calcium content of your soil and the salt content of your soil. The use of sulfur has also been incorrectly acclaimed to break up compacted soils. Sulfur has an acidifying effect on a soil. Adding sulfur to a calcareous soil (soil mostly or partly composed of calcium carbonate) only creates gypsum (calcium sulfate). All of this will mess with your pH level. Don’t use any of these things for compacted soil. Really, the basic solution for compacted soils is to physically manipulate the soil. There are no short cuts when dealing with compacted soil. There is nothing you can just pour out of a bottle or dump out of a bag to fix it.
I guess I’ve said enough about dealing with high traffic areas in your turfgrass. This sort of turned in to a block of instruction on compacted soil.
If what I’ve laid out here doesn’t really apply or does not work, well, perhaps this is one of those battles you should withdraw from and live to fight another day. I hate to say it. Maybe you should do something to manage traffic flow. Raising your garden beds, establishing a walk way, installing a fence or garden wall (like a "hard scape" solution), mulching…these can all be alternatives to having a hard soil bare patch in your beautiful lawn.
Okay, troops. At ease. Let’s talk MULCH. Mulch is important. It is not only aesthetically pleasing, it serves some purposes. Aesthetically, it neatens the appearance of your landscape. It makes your AO (Area of Operation) look more squared away. Mulch really makes your landscape look like you care about the appearance of your quarters or facility. The more functional roles of mulch are: suppressing weeds, retaining moisture, insulating the soil and diminishing soil erosion. As mulch decomposes, it helps soil structure and fertility.
There many types of mulch. Opinions on mulch are just as plentiful. How your landscape “looks” is totally up to you. For example, I’m not a big fan of dyed mulch. Why? Because, eventually, the color goes away. The colorants are NOT harmful. But the colors will fade. The type of mulch you need to use does have some considerations. Does your choice of mulch remove nutrients? Does it change the pH of the soil? Could it be harmful to pets?
First off, I’ll give you my “high speed” recommendation. For my customers in the US Mid – Atlantic Region, I always recommend shredded cedar. I think this is the best. Shredded mulch “locks” together better when the mulch begins to settle. But it still allows good water penetration. Shredded mulch stays in place and decomposes faster than chips. And, the scent of cedar is very pleasing to humans but not very pleasing to pests. Those are my big reasons. The color is usually a tan or light brown which works well with many landscapes.
Just like any other mulches, there are some drawbacks to cedar mulch. The first drawback is, although it takes a long time to decompose, as it decomposes it removes nitrogen from the soil. Okay; so monitor that. You may have to fertilize your plants. This is a good opportunity for some organic fertilizer application. Secondly, cedar can get real dry in the summer. That can possibly, maybe, pose a fire hazard in some areas. If those conditions exist, wetting your cedar mulch may be in order.
Shredded cypress is my second favorite. Some folks are saying that the increased use of cypress mulch has resulted in the increased harvesting of cypress trees in the south Atlantic and gulf coast states of the US. That doesn’t sound like a good thing. But cypress mulch is pretty awesome. It does not remove nitrogen and has all the benefits of cedar mulch. However, folks that care about the wetlands in Louisiana and Florida are really concerned about the unsustainable logging of cypress down there. Some of these experts are saying all the “old growth” cypress is now gone and what’s left are newer trees and the new trees do not have the same desirable benefits as a mulch as the old trees did. So, I’d say, stay away from the cypress, if you can. The cypress forests in our south protect our wetlands and our wildlife.
Some folks in my area use fallen leaves. That’s okay. Shredding them would be better. But, remember, some leaves will alter the pH level of the soil. In most cases it will make the soil more acidic. But its an easy way to use those leaves in the fall.
In fact, that’s when you should put down your mulch – the fall. Its after the growing season. Clean out your beds. Remove all the dead annuals and perennials. Do your pruning. (Be sure to WEED!) Then mulch. It is also a good time to square away your edging.
In another blog post, I discuss using grass clippings as mulch. That’s just as lazy (but acceptable) as using leaves. But, do not use grass clippings from a lawn that has been chemically treated. Definitely don’t put that in your vegetable garden! The chemicals (herbicides, pesticides) may harm desirable plants. You’ve seen me type this a million times – Leave the grass clippings on your lawn! Grass clippings are 90% water by weight. When they are left on the lawn they dehydrate quickly. They are also high in protein and are rapidly decomposed by bacteria and fungi. Grass clippings contain about 4% nitrogen, 2% potassium and 0.5% phosphorous. Other studies have shown that grass clippings can equal up to 3 applications of fertilizer – WITH NO ADDITONAL COST OR WORK! Make sure the clippings are chewed up fairly small – get a mulching mower or a mulching attachment to your mower. It is environmentally responsible!
Wood chips are sometimes free from tree companies or local units of government. Sometimes you have to go get them. Sometimes they will dump a big pile in your driveway. They take up nitrogen and are acidic. Just better hope the trees did not have any poison ivy. And, walnut tree chips have some chemicals that inhibit the growth of many plants.
Straw is sometimes used. I’m not a big fan. Straw can easily blow or wash away. Straw can also have a good deal of weed seeds. It breaks down slower than leaves or grass clippings. You will see straw used as mulch in newly seeded turf areas. That’s normal.
Pine needles are very popular in the south. They also increase acidity but they stay put rather well. Hey, if you got conifers, pine needles look…well, natural around those trees.
Bark nuggets are not my favorite either. They do not stay in place. They wash away easily. And, worst of all, they can become direct fire projectiles if picked up by your mower. But, perhaps in some areas where there isn’t a slope, you don’t mow and heavy rain is not a factor, these could be a choice. Pine bark is the most common.
Cocoa hull mulch is popular. Its got great color, texture and aroma. But this easily blows away. It decomposes slowly. Cocoa hulls are poisonous to dogs and cats and can grow mold on the surface.
Gravel or rock is okay. Guess it depends on what kind of “look” you are going for in your landscape. They do not breakdown, do not need to be replaced, but, they do not help the soil. Better make sure this is what you want. Removing this stuff is awful.
Don’t use rubber. That’s usually from old tires. That has lots of zinc and other stuff that can wreak havoc on your soil. Newspapers are too weird and landscape plastic or fabrics look terrible. Plastic and fabrics are also real difficult to remove when the time comes.
Please, no “mulch volcanoes”. Improper mulching kills trees and shrubs! I’m serious. A mulch volcano is when inexperienced troops pile mulch around the base or stem of a tree or shrub. Placing mulch high around the base of a tree often leads to softening of the bark, disease, fungus, and pest infestation. Proper mulching should be more like an “artillery impact crater” – with the tree in the middle. Okay, okay – so you may not have ever seen an artillery impact crater. How about a doughnut? Ever seen a doughnut? You want water to be able to run down the tree trunk and into the ground, not away from the tree. And, you want water around the mulched area to possibly drain inward as well. Two to four inches of mulch should about do it. Here’s a nice document from the State of Maine:
In one home I had, I did something I later regretted. I decided to put paving stones around my beds. I “elevated” some of my beds. Then I put down a weed blocking fabric and then I covered that fabric with some red lava rocks. (Yes; red lava rocks. It was a phase I was going through.) It looked good for about a season. Maybe not even that long. Everything began to unravel, literally. Removing and disposing of all that stuff was really painful. And, it eventually made my quarters look like Mosul in 2004.
I say, stick to the natural wood mulches. It will make your life easier and make your beds very pleasing to the eye. Unless you have the time, money and resources for a mini Versailles, and André Le Nôtre is your gardener, keep it simple.
I've been running into a fairly significant problem this summer. I've encountered a great deal of POISON IVY (Toxicodendron Radicans)lately. I’ll also include in this discussion poison oak and poison sumac. All of this stuff is mean. My wife came in contact with some in our yard. I had a coworker who almost had to go to the hospital because of it. I am just as susceptible. It is some terrible stuff. Some horticulturalists are saying the cultivars of poison ivy out there now have become MORE toxic than in earlier years, citing increased carbon dioxide in the atmosphere. And, the poison ivy is not just along some remote fence line, way in the back, behind a shed. The poison ivy is right there, in a front yard bed, growing through the existing landscape. How do we deal with, and hopefully get rid of, poison ivy?
The first method would involve what we call “cultural” methods or controls. That is the practice of modifying the growing environment to reduce the prevalence of unwanted pests or plants. First of all, this method may expose you to the toxin. If you are susceptible, you would need to wear protective gear (gloves, long sleeve shirt, breather/mask, etc.). No gaps in clothing. You can also get exposed to the toxic oil “Urushiol”, the plant’s sap, from clothing, tools, or other objects that have been in contact with the plant. You will have to “disinfect” anything that comes in contact with the plant. That is, anything you want to use again. Even dead plants can get you scratching. When it is hot out, you’re perspiring and your pores are open, you are really vulnerable.
Repeated cutting of the plant back to the ground surface will eventually starve the root system and the plant will die. However, repeated cutting increases the chances of exposure to the toxic oil.
Hand-pulling, grubbing or hoeing poison ivy out of the ground are difficult, but can work with small infestations. These techniques are rarely successful on infestations that have been established for two years or more. Best results will be achieved when soils are wet. Pulling roots from dry soil is futile. Eradication will only be achieved if all portions of the underground rootstocks (rhizomes) are removed from the soil.
Then there is “chemical” control. Remember what I said earlier in this blog about SELECTIVE herbicides? Selective herbicides kill specific targets, while leaving the desired plants relatively unharmed. BLUF (Army talk for: Bottom Line Up Front): There is NO selective herbicide that kills poison ivy and does not harm anything else. That selective herbicide simply does not exist. There are some “old wives’ tales” out there regarding treatment; vinegar, coffee, hot water. I’m going to try to keep this somewhat scientific.
Several herbicides can be used to eradicate poison ivy over time. One of the most effective active ingredients is “Triclopyr”, a selective herbicide that kills broadleaf plants but does not harm grasses. But, I say again, it is not FULLY SELECTIVE. It is also good with conifers but it may harm other plants. One common example is Ortho's “Brush-B-Gon” Poison Ivy Killer or Ortho's “Kleeraway Grass & Weed Killer”. The best tactic is to look on the herbicide label for the active ingredient triclopyr. Another selective herbicide possibility for poison ivy control includes products that contain combinations of the active ingredients dicamba and 2,4-D. These are two out of three of the main selective herbicides for broadleaf weed control in lawns (the third being Mecoprop-p). These two active ingredients are commonly packaged together in a variety of broadleaf lawn herbicide mixtures. Each of these active ingredients (triclopyr, dicamba, and 2,4-D) is a selective herbicide that can be used safely on grasses to control or suppress broadleaf plants like poison ivy. However, due to the potential for volatilization and off-site movement, these herbicides should not be applied in locations where other sensitive species grow in close proximity to poison ivy. The other sensitive species could be any woody ornamentals; from azaleas to boxwood.
Glyphosate is another active ingredient that is effective on poison ivy. That is the active ingredient in “RoundUp”. But, glyphosate is a NONSELECTIVE herbicide unlike triclopyr, dicamba and 2,4-D. A nonselective herbicide kills everything and anything. Glyphosate can kill both grass and broadleaf plants, so care must be taken when using this product near trees, shrubs, flowers or other desirable species.
Either selective or nonselective herbicides should be applied during periods of rapid poison ivy growth to ensure maximum kill. One of the best times to apply herbicides to poison ivy is just before the plants are blooming. Although you may apply any of these herbicides at the right time and in the right amount, keep in mind that poison ivy is a tough perennial plant with thick, woody rootstocks, and therefore re-growth and new sprouts are likely to occur. If this is the case, be sure to make repeat applications during the same season or in the following year to achieve complete eradication. Whenever you use any herbicide, be sure to read and understand instructions on the herbicide label before making an application.
I talked about this before, but here’s a review. You may need to know these definitions: Contact herbicides destroy only the plant tissue in contact with the chemical. Generally, these are the fastest acting herbicides. They are less effective on perennial plants, which are able to re-grow from rhizomes, roots or tubers. Systemic herbicides are translocated through the plant, either from foliar application down to the roots, or from soil application up to the leaves. They are capable of controlling perennial plants and may be slower-acting, but ultimately more effective than contact herbicides.
Glyphosate is a systemic herbicide. So is triclopyr, dicamba, and 2,4-D.
A couple more trade names are “Crossbow” (a 2,4-D/triclopyr combo), “Triple Threat Broadleaf Weed Killer” (2,4-D & Mecoprop-p), “Weedmaster” (a dicamba plus 2,4-D mixture) and “KLEENUP” (Glyphosate)
Some of the more “earthy” horticulturists use “St. Gabriel Labs' Poison Ivy Defoliant” (Clove Oil, Sodium Laurel Sulphate, Vinegar, Lecithin, Water, Citric Acid, and Mineral Oil).
You could do a “mix” of cultural and chemical control. Like cut the main stem just above the ground and try to pour the herbicide right down on to or immediately adjacent to the main stem. Try not to pour too much so it leaches into the root systems of nearby plants.
Herbicide application by “painting” (like with a brush) on to the leaves is suitable for some locations.
Never burn poison ivy. If the smoke gets in your lungs, that’s a trip to the emergency room.
Finally, there is a radical solution. But, I guess it is not that radical if you have a real severe infestation. You could transplant your all of the desirable plants out to another location, really nuke the area with an herbicide, and then bring the plants back to their original location. Fortunately, the herbicides I mentioned do not have a long life in the soil. It is not like you’d have to keep your plants elsewhere for several months. Obviously, this has to be done during the growing season wherever you are and there must be ample time for the plants to re-establish themselves.
I guess there is one more possible method of eradication. Goats love poison ivy. You could get a goat.