Lawns

What is Thatch?

Thatch is a layer of decomposed and partially decomposed organic matter located between the soil and green turf grass vegetation. When the bottom portion of the thatch becomes mixed with soil (for example, by earthworms) and is in the process of being broken down by soil microbes it forms a distinct layer called “mat”; an organic layer of greater decomposition. Degradation of thatch into mat is desirable since mat can hold more water and nutrients and as a result has better properties compared to thatch.

Identifying a thatch layer in your lawn is easily done by removing a piece of sod with a shovel and examining the cross section from the base of the turf plants to the soil surface. That is where the thatch and mat will be if it exists. There should be a definite layer, not a few loosely oriented old dead leaves about to be broken down.

Beneficial Qualities of Thatch

The resilient nature of thatch absorbs shock from traffic, yet the surface remains unaltered. In addition, thatch and mat resiliency tends to increase turfgrass wear tolerance caused by the compressive and shearing forces of traffic. It also provides a cushioning effect that helps reduce injuries during outdoor sports and recreation.

Thatch provides an insulating effect near the soil surface, thus protecting the turfgrass growing point (“crown”) from temperature extremes and serves as a barrier between soil and atmosphere that helps to reduce water loss due to evaporation from soil.

A modest layer of thatch has many large pores that allow water to drain readily as well as provide exchange of gases between soil and atmosphere. Thatch also has very small pores that retain water that is available for uptake by turfgrass roots.

Thatch is derived mostly from crown, sheath and stem tissue. The cell walls in these tissues are relatively high in lignin, important in tissue rigidity. Leaves, on the other hand, have lower concentrations of lignin and degrade more rapidly, thus contributing less to thatch development. Returned clippings contribute little to thatch when proper mowing frequency is followed; that is, not removing more than 1/3 of the leaf height at any mowing.

Problems from Excess Thatch

If thatch becomes excessive it is an indication that the turf is “out of balance”; that is, the rate of organic matter accumulation is greater than the rate of degradation. This is often due to factors that cause excessive turf growth like high annual nitrogen rates or high irrigation, or conditions that negatively impact the environment that works to decompose thatch, such as soil microorganisms that help degrade thatch, compacted soils, and persistent wet conditions. Thatch is considered excessive when the thickness is greater than one-half inch in home lawns.

Several problems may occur when thatch becomes excessive. For example, crowns may be elevated above the soil surface in the thatch layer, which is a poor medium for growth. Thatch is hard to re-wet when dry. This may lead to localized dry spots in which precipitation or irrigation runs off rather than infiltrates into the soil, where water is needed especially at high elevation levels. Excess thatch also provides an excellent home for certain turfgrass insect pests and fungal pathogens. Turf with an excessive thatch layer may be prone to scalping since mowing equipment wheels sink into the turf.

Resolving Excess Thatch Problems

To remediate thatch problems, discovering the cause or causes of excess thatch is important. As indicated before, the turf is “out of balance”. Consideration should be given to reducing nitrogen, watering “infrequently and deeply”, improving drainage, maintaining proper mowing height and frequency, and careful use of pesticides. Some turfgrass species/cultivars tend to be heavier thatch producers like fescues vs bluegrass, so renovating or reestablishing lawns with turfgrasses that produce less thatch may be beneficial.

Relative thatching tendency of cool-season turfgrasses:

Thatch reduction by mechanical methods is best performed by hollow tine core aeration followed by redistribution of soil cores into the turf. This promotes biological degradation of thatch by soil microorganisms. Core cultivation or dethatching is best done when followed by several weeks of good turf growing conditions. Target dates are generally around Memorial Day in spring and Labor Day in fall.

Dethatching using a power rake or vertical mower is a secondary alternative, but care should be taken to use the proper equipment that has blades spaced at least two or more inches apart to avoid injury to turfgrass crowns. Dethatching by vertical mowing can create a great deal of debris that must be disposed of or composted.

If a thatch layer has gotten out of control (greater than 1 inch) it is unrealistic to think it can be effectively reduced by one coring or one vertical mowing. The remedy may require spring plus late season coring and vertical mowing until it is under control.

Thatch formation to a problematic depth does not happen overnight. It happens over a few years and depends on the grass type, how the turf is managed, and some unique site conditions that might work against thatch decomposition in the turf/soil system.

Garden Pests

Get the Weeds Out

Get the Weeds Out While They Are Young

Summer Weed Management Strategies

Now is the time when those pesky weeds are really coming up full force in many gardens around the state, particularly if you have had rain in your area lately or have been sprinkler watering your garden. Generally, there is a “seed bank” or supply of weed seeds from previous growing seasons that are just waiting for the right growing conditions to germinate. If these seeds are near the surface from last year or brought back up to the surface from tillage, they will germinate and grow if they get moisture and exposure to sunlight. The easiest time to control them is while they are still young plants. It is much easier to go down a row in a garden to hoe through some seedling purslane before it has begun to creep along the ground and kill it than to wait until the weeds are larger and better adapted to regrow after being hoed out, for example. Seedling weeds have a very small, tender and shallow root system so they are easy to pull, hoe or cultivate out and chances are good that they will not regrow. Warm, sunny weather will give you the best chance for success since those weather conditions will more likely dry out and kill the dislodged and chopped seedlings. Avoid hoeing or cultivating right before a rain or sprinkler irrigation for best success as well.

Shallow Cultivation & Hoeing

Since more weed seeds may still be beneath the soil in your garden, it is a clever idea to let them continue to be covered by the soil, which inhibits them from germinating to some extent. Therefore, using shallow cultivation or hoeing is often better than deeper tillage at this point in the season. Shallow cultivation near our vegetable plants is also less likely to damage the roots of those plants while still being an effective means of controlling young weeds. When vegetable and flower seedlings are still small, hand weeding is probably the best approach, but it is tedious work. I carefully work my way down the row, pulling out the individual weeds among the desirable plants. This is also an appropriate time to thin out excess plants if needed, particularly in beets, carrots and other root crops. Weeding a clear strip about 4-6” on either side of the planted row is generally good enough. Then you can hoe the wider area between the rows without worrying that you are going to hoe out any of the vegetable plants. Hand cultivators or the old-fashioned high-wheel cultivators can also work very well. They will dig more deeply into the soil though, so they may bring up more weed seeds from deeper in the soil.

Rectangular Hoes

There are several various kinds of hoes. Most people are likely familiar with the rectangular shaped hoes. These often work best for digging holes for planting transplants or hoeing out larger weeds. The fact that the hoe blade is usually at about 90° to the handle makes them more difficult to use for shallow cultivation.

My favorite hoe is the stirrup, oscillating or scuffle style hoe works even more efficiently in that it can do the same thing both in the pulling and pushing stroke, so you can cover about twice the area in about the same time.

Rototilling

Rototillers are another popular means of weeding the garden. However, they probably should not be used until the vegetables are a bit larger, later in the season. It is very easy to bury small vegetable plants with soil thrown up by a powered tiller. That soil may smother young plants, or it may contain diseased debris from last year that may then inoculate your young vegetable seedlings with the disease. So, consider hoeing the garden for the first round of weeding, then move to the rototiller for the next round of weeding if you wish.
Mulching

Of course, mulches are a great option. Mulches help to keep down weeds by shading the soil, reducing the chances that seeds can germinate and grow. Straw, old alfalfa, or grass clippings are probably the most common types of organic mulch, but you must be careful not to use any materials that might have been treated with a broadleaf herbicide. Otherwise damage to sensitive plants like tomatoes and potatoes is likely to occur.

Some people might be tempted to use herbicide in the vegetable garden to control weeds once their vegetables are growing. While this might seem like a quick and effortless way to kill those little weeds, you could do much more damage than good, especially if you try to use something that is not labeled for use in a vegetable garden. Potatoes and especially tomatoes are especially sensitive to spray drift from broadleaf herbicides that have active ingredients like 2,4-D. They cause malformation of leaves, stretching of veins and curling of petioles and stems. Many herbicides are not very selective in what they kill and, in some cases, are non-selective, meaning they will kill or damage pretty much anything that they encounter. The fact that we intend to eat our vegetables makes this issue much more important. If a vegetable crop is contaminated with a non-registered herbicide that produce should not be eaten, even if the plants look like they “grew out of” the damage caused by the herbicide application or drift.
Crabgrass Management

Crabgrass seedlings are also now showing up in lawns and around garden beds also, and you do not want them to go to seed. It is generally easy to identify them by their wider and lighter-green colored leaves. It will often show up in bare areas in lawns or along garden beds. If you are still seeing crabgrass seedlings showing up in your lawn, you might still be able to control them if they are still at a young enough age.

Post-Emergent Herbicides

Look for a lawn herbicide that says it will provide post-emergence control of crabgrass on the label. It will likely state that it contains the herbicide quinclorac but there are a few other active ingredients in various products available as well. Follow the label to see how to safely spray them over lawn grasses to kill the crabgrass without damaging the desirable lawn grasses. Once crabgrass grows to a point where its stems begin to sprawl along the ground, root down and produce seed heads, there really is no effective treatment that can be used. It is best to remember to apply a crabgrass preventer to those areas of the lawn to prevent those weed seeds from germinating next spring.

DIY Projects

Fall in Love With a Pergola

Fall in love with your yard again with a pergola.

For homeowners, beautiful landscaping can make a significant difference. While lush plants and verdant lawns are common outdoor features, adding a structure to complement the greenery in your backyard is a popular move, too. Try a pergola!

What is a pergola?

 

Pergolas are wall-less structures that consist of vertical posts that support a roof of slatted beams or lattice. Unlike an arbor, which typically has rounded arches, pergolas are made up of straight lines. While these structures are traditionally free-standing, some homeowners attach them to the side of a house for added support.

Why do people love their pergolas?

Unlike other types of backyard structures that come with closed roofs like gazebos, a pergola is an open-roof feature that provides filtered shade. Both people and plants love them because they do not block all the sunlight. They’re also easy to install on any flat spot in your yard, so you can get creative with the placement and you can order complete kits from many stores like Menards and Walmart.

A pergola can function as a trellis for climbing plants toward the back of your yard. Need to create a little me space in your backyard? A pergola can help you carve out a little separation for an outdoor room.

Pergolas can also benefit a yard by offering good bones to a landscape all year-round and during winter in cold-weather climates, a pergola can add visual appeal to a barren yard.

Pergola design ideas

Patio or deck overhang: If you are looking for ways to dress up a concrete patio or a wooden deck, a pergola will turn what you have into a fresh new feature. For a little privacy or protection from bugs, consider adding fabric walls. Curtains, sheers, or netting rated for outdoor use will get the job done. If you prefer hard walls, wood lattice works.

Cover for a front porch: A pergola over a front porch is an architectural element that can add a little value—and curb appeal—to your home. To embellish it, hang potted plants or climbing vines. For a dash of stylish flair in the evening, you could wrap a pergola with outdoor lights.

Outdoor room: Outdoor living spaces are trending, and pergolas give you a great structure and an unlimited canvas for personalization. Virtually any spot in your yard can be transformed into an outdoor room for gardening, dining, napping, or reading on gloriously warm days.

Walkway cover: Have a detached garage? Make the most of the walkway between your home and garage with a pergola that offers a little break from the sun.

Entryway overhang: Homes that lack fascinating exterior features do not make a stellar first impression. A pergola over a front door will instantly beautify a plain entry.

Outdoor entrances: Frame the opening to your side door or backyard walkway with a small pergola covered with climbing plants. Ivy, morning glory, and climbing hydrangea are all good choices. If you prefer to plant something edible, you could go with climbing vegetables like tomatoes, cucumbers, and climbing pole beans.

When planning to install a pergola, you should know that wooden pergolas are the most common with pressure-treated wood being the most economical, however, plastic ones have come on the market in many colors