Hackberry Trees: Dying or Under Attack?

Hackberry trees in Denton County are being hit by hard by moth larvae. The small green caterpillar eats the flesh out of the leaves, leaving only the veins. The defoliation can make a hackberry tree appear as if it is dying, but it is not.  

Pest populations fluctuate along with predator populations.  The last time we saw this pest was in 2015.  Hackberry trees in southern Denton County were defoliated by the same small green caterpillar that year and we haven’t seen them in large numbers until this year (2022).

A healthy tree can withstand a complete defoliation. Next spring the tree will leaf out normally. New leaves might even form with rain and cooler temperatures in the fall.

What Can Be Done?

By the time you see the damage, the caterpillars are done feeding and any treatment just kills the caterpillar’s predators and does nothing for your tree. And while treatment is not recommended, you can help your tree recover from the stress of the hot, dry weather in recent months.

Here are a couple of suggestions:

• Ensure your tree is getting sufficient water at the root zone. Check the soil for dryness. Consider whether your sprinkler system is doing its job. (See this post for correct watering practices.)

• Add compost to the root zone. (For more information on composting, click here.)

• Consult with one of our ISA Certified Arborists about whether or not your tree is in need of fertilization or soil aeration or is perhaps experiencing stress from multiple environmental factors.