Sirhornsalot
**The Official Horn Sports Landscaper and Landscap
- Joined
- Nov 6, 2013
- Messages
- 33,450
Young Aphids, above.
Aphids, Scale, Spider Mites – Oh My!
While sitting near a row of Crape Myrtles a few years back at my son’s little league football practice, I overheard a family sitting in lawn chairs underneath those Crape Myrtles.
“This tree is dripping sap,” said one lady. “That is why you feel wetness dripping on you under these Crape Myrtle.”
Being one who can’t always keep my mouth shut, I walked over and introduced myself and told them they were mistaken about the dripping coming from the Crape Myrtle.
There will never be a time in the life of a Crape Myrtle where it will weep sap from its canopy.
So I told them it wasn’t tree sap that was hitting their exposed arms and legs. Instead, the moisture substance is created by a pair of insects which are feeding on the branches of the Crape Myrtles. Both Aphids and Scale secrete the substance on the limbs and leaves of a tree, in this case a Crape Myrtle.
This substance is sugary sweet (so they say, lol) and attracts other insects, such as ants, spider mites, and the predator insects which feed on those insects, such as wasps, hornets, spiders, etc.
It can become a real mess.
Crape Myrtles are not native to Texas. They are accustomed to a more humid environment and more frequent rainfall than what we experience here. So they are vulnerable to predator insects if they are not well taken care of.
There are basically three insects that prey on Crape Myrtles (and some other types of trees, too). They are:
Scale, looks like a white crusty substance but is actually a destructive insect.
1. Scale. You’ve probably looked at this before and thought “what is that white crusty stuff all over the branches?” That white crusty stuff that never appears to move is an insect called Scale. Scale spends its time extracting the moisture out of the host plant (Crape). Over time, these insects multiply and can become widespread. The health of the tree declines, especially during a hot summer, as the effects of Scale take their toll.
2. Aphids. These are small bugs that congregate on the leaves and trunks of Crape Myrtles (and other trees, too). They are easily seen with the naked eye. You’ll often find them on the underside of the tree’s leaves or toward the bottom of the trunk. They, too, extract moisture from the host Crape. They secrete that sugary substance, much like Scale does.
A small nest of Spider Mites, above.
3. Spider Mites. These are very small and hard to find. You can detect them by the unique webbing on trees. These are mites which feed on the moisture of the tree. Their webs, unlike spiders which are created to catch insects, are built to take them from one place to another. Being a creature feeding on tree moisture, it has no interest in catching anything. It just needs to move from limb to limb. Their nests can look a lot like regular webs but are very thick and protective of the eggs inside.So when spraying for these insects, you will want to spray on the undersides of leaves, too.
How to Detect
From a distance, you will be able to detect Aphids because of the shiny, wet-looking leaves they create on Crape Myrtles. These leaves literally look wet, even though there’s no rain to make them wet. Recognizing this is key and should prompt a closer examination of the trunk and leaves.
In a closer look, you’ll see white crust up and down the bark. Scale. Aphids are small Beatle like insects which can be brown, black, green. They hang out on both sides of the leaves, and also up and down the trunk.
Spider Mites are first noticed by their webs which often flow in the wind from the tree’s canopy. You will struggle to see the actual spider mites until you spray the tree and watch as they slowly fall to the ground. It can look like it’s raining spiders.
What to do
All three of these insects can be controlled using a product featuring bifenthrin. There are dozens of products that have this ingredient. It is best used in liquid form and sprayed, as it is a contact kill, needing to make contact with the insect in order to kill it. If you’re not comfortable doing this yourself, then by all means contact a professional. We must be careful using Bifenthrin and not use it when you see honey bees around.
Chinch Bugs are Back!
Unfortunately, the discussion on insects does not end here.
Already we’re seeing the emergence of Chinch bugs in lawns in North Texas. These critters can take out a lawn in just a few weeks time if left unchecked. They will prey on Bermuda, St Augustine and Zoysia turfs.
First signs you can see to determine their presence will be areas that have not grown since being mowed, while surrounding grass has grown like normal. This is evidence that Chinch bugs are present and have begun feeding on the turf in that area.
Chinch bug damage is easily recognized for its signature bronze hue color. Over time, the moisture is extracted from the grass plant by the Chinch bug, taking the grass down to nothing.
Chinch bugs will only feed in the sunniest, hottest locations in the lawn. You will not have problems with Chinch bugs in shaded areas of the lawn. You will notice deteriorating turf that is turning that bronze hue color I mentioned.
Chinch bugs will locate themselves close to concrete curbs, sidewalks and driveways because the concrete reverberates heat, which is what the insect wants. They will position themselves at the ends of the grass blades, biting into the sap system (80% water) of the grass plant. It will extract moisture until the plant has no more. They then move on to the next blade. With hundreds or thousands of these insects working at the same time, notiiceable damage is present within a week or so.
Like the Crape Myrtles insects, we treat Chinch bugs with Bifenthrin products in liquid form (spray). You must treat twice, the second treatment being one week later. This will ensure that any of them which may have hatched from eggs in that time will get knocked out.
Other Items This Month
– July is here so you are safe to trim any Oaks you have that need trimming. We do not trim Oaks from March through June each year as that is when the Oak Wilt pollen is present. That is behind us now so we can trim any Oaks.
– If you still haven’t put down fertilizer on your lawn, it is too late to do it. July is here and so is the 100-degree temperatures, so applying fertilizer now could result in burning the lawn up. The next application time will be the third week of August.
– I advise against trimming shrubs this month as we experience the extreme heat. Trimming them now can set them up for stress as leaves can become tinged and burned.
