Q. My peach tree has started looking sad – not as many leaves as last year, leaves are turning yellow, not much fruit, and there are little holes in the trunk where sap has oozed out and dried. I’ve had it for at least 15 years, and it’s always been productive. What is happening, and how do I fix it?
Unfortunately, peach trees are not very long-lived. Most will show signs of decline after about 15 years, even if they were previously vigorous. Some environmental factors, such as drought (or irrigation failure), lack of winter chill, excessive cold, or excessive heat can stress a tree and leave is more susceptible to disease and pest damage.
The little holes in the trunk of your tree indicate the presence of shothole borers, a common pest affecting peach trees. These are the larvae of a small beetle that lays its eggs on the bark of the peach tree. When the eggs hatch, the larvae bore through the bark and into the cambium. If the infestation is not excessive and the tree is not water stressed, it can often expel the borer through sap pressure. A drought-stressed tree lacks this ability, so the borers remain to do their damage. Usually, you will see globs of dried sap (amber) on the trunk where the holes have been made. Borers will often target sunburned trees where the bark has peeled away, leaving an open wound.
Once a tree has been infested, there is no effective treatment. If the infestation is limited to a branch (or a few branches), pruning may limit the damage. Dispose of the infested wood right away to avoid further spread. If the main trunk has been affected, especially in an already stressed or declining tree, total removal is the best action.
Q. How can I get rid of Bermudagrass in my lawn?
Bermudagrass is sometimes used as a turfgrass, particularly in areas with very high foot traffic. Most of the time, though, it’s considered a weed, especially in lawns. It spreads both by its wiry stolons (stems) and by its rhizomes (underground roots). If you pull it out, you may have gotten the stem and part of the root, but it will come back with a vengeance if there’s even a tiny bit of root left behind. No wonder it’s called devilgrass!
In undisturbed soil, the roots are relatively shallow. If the turfgrass is healthy and deep-rooted, you can try pausing irrigation or irrigating deeply and infrequently to starve the bermudagrass. If the bermudagrass is growing in otherwise bare areas, herbicide application may be the most effective solution. Most of the time, you will need to reapply several times to completely eradicate it.
Los Angeles County
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Orange County
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Riverside County
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San Bernardino County
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