Category Archives: Pests of landscapes
Fire ant season reminders
With a little bit of rain and warmer temperatures fire ant mounds are popping up throughout Texas and the southeast. Spring mound season is an excellent time to think about controlling some of those larger mounds with a mound treatment of your choice. Despite the warm days with air temperatures in the 80s and 90s, soil temperatures are just climbing to levels where fire ants are thinking about foraging for food. This means that in some areas it may still be a little early for applying fire ant… Read More →
Oak gall midges
I recently received a sample of thousands of tiny (1-1/5 mm) maggots collected from a local yard. The sample was collected by Susan Bailey of Plano, who noticed writhing masses of these worm-like critters on her driveway and ground under a live oak tree. Now anyone who lives around live oaks knows that for the past ten days or so these trees have been showering the world with pollen and the senescent catkins (male flowers). These tiny larvae are occasionally reported under oak trees shortly after flowering. After… Read More →
Now’s the time for dormant oils
Dormant season applications of horticultural oil can be an effective tactic to kill scale insects and their eggs during the winter months. But with the rapid onset of warm spring weather, the window of opportunity is relatively small in north Texas and many other parts of the state. Armored scale like obscure and gloomy scale are especially difficult to treat during the summer months, so the dormant season when leaves are off the trees is an excellent time to treat with a dormant oil. Oils are physical poisons,… Read More →
Texas Invasives website includes emerald ash borer
In case you haven’t heard, there’s an invasion going on. It’s not something you are likely to notice walking out the front door; but it’s taking place on a scale that would have seemed incredible a few years ago. Anyone who’s been stung by a fire ant has encountered it and nearly every field biologist is painfully aware of it. It’s an invasion of exotic plants, insects and animals, and it’s never been more serious. It’s hard to completely escape the news stories about Asian carp and “killer… Read More →
Ash flower gall in the fall
Last week our forestry specialist sent the image shown here with questions about it’s possible cause. The culprit is a mite, often referred to as ash flower gall. Like many pests of trees, ash flower galls may be more evident some years than others. The mite actually lives in the male flower parts of ash trees, and the gall is a distortion of those flower parts. Because only the male flowers are attacked, tree health is not affected by infestations. However, many people consider the galls themselves unsightly,… Read More →
The pros (and cons) of “Green” golf courses
A mini-debate has been running recently among the small community of entomologists who work with insect pests of turf and ornamental landscapes. It has to do with the growing emergence of green golf courses and a recent story/video at time.com on the Chambers Bay links golf course on Puget Sound in Washington. The discussion was interesting and reveals some of the subtleties of varying opinions on the green movement. Chamber’s Bay is a sustainable, all-fescue, Scottish-links-style course that was built on a reclaimed gravel pit. The course uses… Read More →
U. S. Department of Agriculture declares August invasive species month
The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS) this week proclaimed August as “Invasive Plant Pest and Disease Awareness Month.” According to a press release, beginning this year, APHIS will engage the public each August to increase understanding about the risks that invasive plant pests, diseases and harmful weeds pose to America’s agricultural and natural resources. Texas has more than its share of exotic pests, and more are expected to arrive over the next few years (Reminds me of the bumper sticker, “Not a… Read More →
New disease of walnuts reaches Midwest
A little over one hundred years ago an estimated 4 billion chestnut trees blanketed the eastern hardwood forest of the U.S. Between 1900 and 1908 an accidentally introduced, and most devastating disease, called chestnut blight, was introduced. Forty years later, it was nearly impossible to find a single mature chestnut tree in the eastern U.S. The chestnut illustrates the rapid changes possible with invasive pests. It may, or may not, foreshadow what is about to happen with another important tree, black walnut, Juglans nigra. One of our most… Read More →
When is your evergreen a lost cause?
In one sense bagworms are not an especially devastating pest. They have only a single generation each year (therefore are relatively slow to establish) and they don’t spread very quickly, because the female bagworms are wingless. On the other hand, they are well protected from many pesticides by their tight, water-repellent bags. They are also one of our few chewing pests that will tackle evergreen trees and shrubs. If you’ve ever seen a deciduous tree (one that loses its leaves in the fall) defoliated by caterpillars you may… Read More →
The gall!
Last week I got called to look at a tree that supposedly was turning brown from a tiny gall-making fly called Macrodiplosis quercusoruca, or vein pocket gall fly. I was skeptical that the leaf tissue death (necrosis) I saw on a small sample was caused by the insect. I have seen leaves disfigured and trees thinned by vein pocket gall, but had never seen a tree so heavily infested that the canopy was turned brown. When I saw the tree I was convinced. Most of the leaves in… Read More →
