The Magic Ingredient

Soon we can look forward to shorter days and a much-anticipated respite from the summer heat.  Like most people in the United States, we South Texans call this time of year fall, so-named for the leaves that some landscape perennials will shed as part of their winter survival strategy.

While the shedding of their lealonghorns-and-bluebonnetsves means that deciduous plants are about to go on an involuntary winter diet, a veritable buffet will befall a few trillion hungry soil-borne bacteria and fungi.   As this windfall of detritus enriches the soil with a population explosion of microscopic creatures, a host of other small animals such as mites, sowbugs and beetles will move in to clean up.  Birds recognize this as an opportunity to unearth a steady supply of beetle protein tucked away under the decomposing organic matter.

In an effort to maintain a tidy lawn, we often make the mistake of raking everything up and hauling it off to an already overburdened landfill.  This removal of organic matter robs your landscape of valuable nutrients.

While three to five percent can be expected in the eastern part of Texas, most urban soils only contain around one percent of soil organic matter by volume.  Composted organic matter aerates the soil, increases its water and nutrient holding capacity and creates a rich environment for plant root growth.

Increasing the amount of organic matter in your soil is easy to accomplish.  Rather than raking up all of your leaves this fall, use a mower with a mulching blade to chop them into tiny pieces.  The force of a properly setup mower will literally inject new life into your soil.

If there are too many leaves for your mower to contend with, put them in a compost bin or rake them into a corner of the lawn.  Place an old piece of carpet or plywood on top of the mass of leaves, occasionally adding water and turning the pile to speed up decomposition.  Don’t place the composting material against plant stems, fences or the side of your home.

Chopped leaf litter can be used as topdressing which will slowly decompose to feed nearby plant roots.  So when you plant out your violas, ornamental cabbages, and snapdragons for a little fall color, may I recommend that you plant them in a bed of chopped up leaves.

The Scoop on Poop

The concern with animal manure composts begins with the recipe and ends with the how it is processed and where it is used.  In Fact, the most important considerations for any garden compost, whether it comes from a plant, an animal or a combination of the two, is knowing what it is made of, how it is made and how it is used.  What follows is a word of caution and a few reasons gardeners may want to stick to “best” soil management practices by incorporating plant-based composts into their garden rather than “good” management practices using animal manures.

Compost is decomposed organic matter.  It is used by tiny soil organisms as food.  Bacteria, fungi and small insects living in the soil eat organic matter and leave behind a rich byproduct that plants take up through their roots.  Almost anything can be composted if given enough time and the right conditions.  However, when it comes to gardening, there are some things that are good to put into a home compost pile and some things that should be left out.

When thoughtfully included as an overall part of soil management, animal manures may make a valuable contribution to the garden.  Animal manure compost is often added as under the assumption that they make an excellent “organic.”  However, any type of compost including animal based material is more appropriately added to soil as food for the microbes.  It is the activity of these tiny underground animals that brings soil to life.  Manure is often freely available from facilities that accumulate large amounts of animal waste.  When a gardener is on a budget, adding animal manure in small and carefully planned amounts may benefit gardens.

On the other hand, large amounts of animal manures incorporated into soil may create more problems than solutions.  Consider horse manure.  With horses, food moves quickly from one end of the digestive system to the other.  Of course, horses eat plants.  Anyone who has ever taken a look at fresh horse manure can testify to seeing undigested plants in the stool.  When it is not properly “hot” composted, horse manure will contain viable weed seeds along with the undigested plants.

Sometimes, horses eat plants that have been sprayed with herbicides to rid a pasture of weeds.  Horse manures from a source such as this will still contain those chemicals.  These broadleaf weed killers are toxic to garden plants.  Nightshades such as tomatoes, eggplants and peppers can be killed outright by leftover herbicides in animal manures.  When not killed, ornamental plants may become distorted beyond recognition while vegetable plants will be less productive.

The high concentration of salts in horse manures will slowly increase in the soil as each successive application is worked into the garden.  These salts may eventually reach toxic levels.  Even before salt concentrations hit toxic levels in soil, they will begin to inhibit the uptake of other vital nutrients by plants.

It is difficult for home composters and even livestock facilities to compost some organic materials properly.  Hot composting occurs when organic material is layered in a specific manner which will increase its temperature and destroy most weed seeds and many herbicides.  This involves layering large amounts of carbon rich materials with small amounts of nitrogen rich materials.  Commercial composters are successful at reaching higher composting temperatures because they actively turn, water and aerate their compost piles to ensure a high quality product.

Cold composting on the other hand is a more passive method of simply piling up organic material and allowing it to break down without much input from the composter.  Feed lots, horse stables and other livestock facilities rarely have the time or experience to generate a garden-ready product.  Their business is to handle livestock which is accompanied by an ever increasing by product they cannot effectively compost.

Many of these animal handling facilities wisely sell or give their waste to commercial composting operations.  Most commercial composting companies have the experience to process animal manure properly by adding it to the massive amounts of plant-based material they receive.  Professional composters are often happy to provide their clients with information about their composting process and an analysis of their product.

While an offer to pick up all the free animal waste you can haul sounds like a treasure that can’t be passed up, think twice before shoveling it into the back of the family truckster and taking it home to plow into your garden.

Fix That Plant Or Rip It Out

Stop landscape problems before they start.  Once your turfgrass, vegetable garden, shade tree or flowerbed becomes pest-ridden, you may have lost the upper hand in using the most environmentally friendly pest control methods.  Integrated pest management (IPM) is the name given to a holistic approach which begins with selecting the right plant for the right place and ends with plucking the hopeless thing out of the ground once all else fails.  Before we reach that frustrating conclusion, let’s look at six “do’s and don’ts” that may allow you to get on with the rest of your busy life a little sooner.

Do put the right plant in the right place.  Has anyone ever invited you to gaze at their lovely West Texas azaleas?  Probably not!  Azaleas prefer acidic soil.  They’ll decline quickly in the high pH soils of the Permian Basin.  Understanding the environmental needs of plants such as temperature tolerances, pH range, water requirements and so on may save you a lot of anguish.  Fortunately today, most plants sold in nurseries have a tag that provides basic growing conditions.  However, that’s just a starting point and shouldn’t be your sole source of information.  An excellent resource that provides detailed information about the plants we love is http://aggie-horticulture.tamu.edu/.

Do keep your plants healthy.  This sounds too simple to be true but once you’ve done your research and picked up the basics of caring for your new plant, stick to what you learned.  I love experimenting with recipes, putting my special twist on each dish.  The outcome is usually less than perfect.  That’s fine when it comes to food but plants are living things that thrive or decline under known conditions.  Thorough knowledge of these conditions is often gained only after years of extensive trials.  Stick to the recipe by applying the research-based advice of AgriLife Extension professionals.  Its the surest way to minimize plant stress and keep pests from ever getting a foothold.  Stressed plants are like people (sort of); they can develop a weak defense response.  Insects are able to see or smell sick turf, trees, vegetables and ornamentals.

Do get to the root of the problem.  OK!  So you’ve done everything right and you still spot hundreds of insects attached to a prized tree.  Don’t run for the bug spray too soon.  The next step is to identify the insect.  This is where you go back to the information you learned about your plant before you got it home.  Most information sources include a list of potential pests.  If you’re having trouble figuring out what it is, bring a sample of the infected plant by the AgriLife office.  It may turn out to be only a minor problem or no problem at all.

Do begin treatment options when necessary.  For the sake of discussion let’s say you discovered that your afghan pine is playing host to the pine tip moth.  This could be a problem.  Now what?  If the tree looks otherwise healthy, you may choose to do nothing at all.  Remember that many pests are only a problem for plants weakened  by things like drought, overwatering, weed killer, or excess fertilizer.  Healthy plants often tolerate small populations of unwanted residents without ever being worse for the wear.  But if your tree’s growth seems a little stunted, has fewer cones than usual and its needles are turning brown at an alarming rate, act fast.

Do avoid pesticides if possible.  If the tree is stressed by drought, increase the amount of water it receives.  Remove and destroy the infested buds and twigs several inches below the injured areas. Put three or four inches of mulch over the root zone to moderate soil temperatures and conserve moisture.  The goal is to increase vigor and reduce damage.  This is true for any plant but it doesn’t necessarily mean adding fertilizer.  Nitrogen fertilizer causes foliar growth which may signal a more nutritious feast for pests.  Stick to improving the tree’s growing conditions.  You may need to resort to the use of pesticides but don’t go for the nuclear option first.

Don’t bring a gun to a knife fight.  Contact your local AgriLife office or find an Extension publication that offers control options for the identified pest.  Start by considering the least impactful yet most effective pesticide.  You may discover that “organic” pesticides have a greater risk of negative impact on the environment than synthetic controls.  This is more likely to be true when repeat applications are necessary.  Sometimes it’s wise to remove heavily infested plants to protect others nearby.  Fortunately, you’ll learn that pine tip moth can be controlled with spinosad which is considered an “organic” product.  But better still, you’ll learn that there is no pressing need to treat pine tip moth late in the summer.  Your best option may be to wait until Spring and treat if necessary when the overwintering larvae emerge and begin their life cycle over again.

Plant Water Use From The Ground Up

Plants are more than eighty percent water by weight.  However, only a very small fraction of the water that moves through a plant is kept.  Plants are conduits that allow water to move from the soil, into its vascular tubes and exit through special gates called stomata which are located on the lower surfaces of leaves.  The water transport system, called the xylem, is a “straw” made of cells stacked directly on top of one another.  Depending on temperature, sunlight, wind and other factors, stomata will either close to slow the movement of water through the xylem, or they’ll open and allow the leaves to “sweat” water vapor into the air.

Water is the engine of all plant life.  It’s everywhere.  Even the air we breathe, work, and play in holds enormous volumes of the stuff (humidity).   It drives storms and buffers temperatures as it changes from a solid state, to liquid, to gas, and back again.  Only three percent of the Earth’s water is fresh.  The United States Geological Survey estimates more than two-thirds of fresh water is frozen and as much as thirty percent is underground.  A tiny three-tenths of a percent is readily available as surface water.

Imagine for a moment that you’re a molecule of water in the soil.  To a plant, you’re the most important yet limited natural resource it needs.  You’re made of a single oxygen atom flanked by two hydrogen atoms.  Your unique physical and chemical properties cause you to stick like glue to nearby molecules.  Thin cells on the outer surface of roots, called hairs, reach into the surrounding soil and draw you in.  Each molecule of water is taken up by a root hair and added one at a time to a slow moving microscopic river of dissolved minerals.  The stream flows against gravity as it moves toward the leaves.  Plants don’t directly spend any energy to move water in this way.

If a root hair pulled you in during the cool of the morning, you might feel the inward pressure of neighboring molecules crowding against you.  Plant cells are full of water in the morning.  Overnight, while the sun and wind are less intense, the stomata are closed and less water vapor is lost at the leaf surface.  A bottleneck of sorts develops.  You may even hear popping and cracking sounds of nearby cells as they bulge from water entering faster than it is leaving.

On the other hand, if you moved into a root hair during the hottest part of the day, you may feel a strong tug from the water molecule that entered just before you.  In turn, you’d be pulling hard on the one following you.  During hot summer days, evaporation through stomata often happens much faster than water can be taken up by roots.  If you were a water molecule under these conditions, you may occasionally hear the retort of entire columns of water in the xylem as they snapped like overstretched rubber bands.  Plant cells near the break would soon dry out and die if the water stream isn’t restored.

Left to its own devices, the water status of a plant is partially dependent upon its ability to react to injury, drought, heat, cold, poor quality water and any number of other environmental conditions.  Some of those conditions in West Texas include a soil pH above of 7.0 (alkaline), fourteen or fewer inches of rain annually, and temperatures that occasionally reach over 110 degrees Fahrenheit or dip below 25 degrees Fahrenheit.  While all of these must be considered, it is the quantity and quality of water which imposes the strongest limits on our selection of perennial landscape plants in the long run.

There is little that a homeowner can do to reduce the loss of plants from water stress.  Those things that we do have some ability to influence belong in one of three broad categories; we can select plants that perform well in our region, we can “train” landscape plants to use water more efficiently, and we can influence the availability of soil water.  We’ll take a look at these things in a second installment.

To learn more about the fascinating world of plants or how to become a Texas Master Gardener, contact your local Texas A&M AgriLife Extension office

 

A Case Bearing Closer Inspection

If you own a pecan tree one of the pests you’ll want to be on the lookout for is the pecan nut casebearer, which is among the most important economic pests of pecans.

The larvae of the casebearer bore into and gobble up developing nuts. When shrunken pecan nut clusters are spotted on the tree, it is probably due to first generation casebearers. Scouting for these pests should begin just a couple weeks from today.

The first generations of casebearers begin showing up in early spring, emerging as rather plain looking half inch long tan moths. The can be identified by a dark stripe on their wings just behind their heads. Overwintering larvae from third or fourth generations emerge out of their protective silk cover to feast on tender buds before nuts develop. They soon pupate into their adult moth form and mate, eventually laying as many as 150 eggs in a season.

Casebearer eggs are white, turning pink and occasionally red before they hatch. The first generation is the most damaging. Larvae will feed for about five weeks, then settle within a nut and pupate into an adult moth. A lone larva can quickly destroy an entire nut cluster. Second, third and fourth generations cause less damage. As these later generations surface, they are quickly filled up by feeding on larger nuts making them likely to move from there to other nuts. Hardened shells also provide more protection from damage during later generations.

Scouting makes use of traps baited with the scent (pheromones) of females. The traps fool male moths into landing on a tacky surface where they can be spotted. Once monitoring reveals that moths are being caught, you should begin inspecting the nut clusters for eggs. Inspection of nutlets should be done throughout May. If the tree is used for production rather shade, then insecticide sprays may be needed when more than ten percent of the cluster have eggs. If the tree is being grown for shade only then controls aren’t necessary. Casebearers don’t usually cause serious injury to pecan tree health. In fact, they may provide a benefit by reducing the amount of weight that limbs support.

Choose The Right Grass

Warm season turfgrass performance is far superior to cool season species such as fescue, bluegrass and perennial ryegrass under the relentless heat of West Texas.

You’re probably familiar with varieties of Bermuda and St. Augustine grasses which have successfully blanketed many of our lawns for years. Buffalo grass has also gained some popularity for its ability to survive heat and extremely low amounts of supplemental irrigation even under the most extreme conditions. However, you may not be as familiar with zoysia grasses.

The erratic weather patterns of the last few years have been responsible for a slight increase in the number of lawns that have turned to the less familiar varieties of zoysia as an alternative West Texas turfgrass.

So how has zoysia held up? Generally, Zoysia has performed well in situations where maintenance practices are adjusted to accommodate some of its important differences from other warm-season species.

I’ve seen empire zoysia look great when irrigated with low quality well water in both sun and dappled shade conditions. My good friend Gloria has been growing zoysia under the deep shade of her live oaks in Midland for decades.

Empire appears to be much more shade tolerant than celebration bermuda grass, which has been reported to tolerate up to 30% less sun than common bermuda. But be warned, not all zoysias are the same.

A study done by researchers at Texas Tech University examined zoysia’s ability to grow in shade. Of the six varieties tested, scientists identified two — shadow turf and diamond — that continued to grow under 90% shade while the others declined.

One weakness with zoysia is its slow growth rate. It’s not a perfect turf for high traffic locations such as athletic fields, city parks or active little feet in back yards.

Under heavy shade it will require some extra fertilizer and should be allowed to grow slightly taller than its recommended mowing height as its leaf blades can capture more sunlight. Another drawback is zoysia’s tendency to green up later in the spring and go into dormancy a little earlier in the fall than most other warm season turfgrasses.

However, in shade, the benefits of zoysia outweigh its shortcomings and it will be easier to maintain and keep alive than cool season turfgrass under most West Texas conditions. Local nurseries have been ordering enough zoysia sod to meet recent demand. Its growth in popularity, although sluggish, may mean that we’ll see it in stores this spring as well.

 

The Backbone of AgriLife

The Texas A&M AgriLife Extension service is a cooperation between federal, state and county governments that has served the United States for more than 100 years.

We’ve been working for Americans longer than Alaska and Hawaii have been part of the U.S.  AgriLife opened its doors in 1914 after President Lincoln signed into law, a congressional act establishing a network of educational branches for the land grant institutions authorized for each of the forty-eight states comprising the U.S. at the time.

Today, Extension serves all 50 U.S. states and territories. In our great state, the purpose of AgriLife has always been to improve the lives of Texans by delivering practical research-based education on local issues.

These issues are identified by you. In other words, you tell us what you want addressed. AgriLife has Extension agents working in 250 of the 254 counties in Texas.

In Ector and Midland counties, AgriLife agents provide education and resources for gardening, landscape design, healthy living, water conservation, agricultural land use, youth leadership and development and much more.

Agents are subject-matter specialists who offer knowledge gained through practical experience.  If they don’t have direct familiarity with a topic you’re interested in, they’ll have access to it through a knowledge base involving A&M faculty, specialists and trained volunteers.

Among the most impressive of AgriLife’s volunteers are the Texas Master Gardeners.  Master Gardeners are locally trained by AgriLife as educators in all topics related to horticulture. Every year they give back thousands of hours to their community by maintaining horticultural demonstration sites, teaching garden classes and making site visits to solve homeowner problems.

AgriLife’s youth development program relies on the extraordinary talents of adult leaders for our 4H program.  These volunteers assist in countless projects that teach young people confidence, leadership and life skills.  Projects in shooting sports, photography, culinary arts, livestock and textiles are just a few of the many activities that keep young minds actively engaged and learning without relying on a smartphone. Everything AgriLife does is designed to enrich your life by improving the quality of your health, saving you money and showing you how to make the most of your time.