Summer Pests

The pests of summer are coming if not here already.  Keep on eye out for grasshoppers, codling moths and IPS and bark beetles.

Grasshoppers can be voracious eaters of just about everything.  There are chemical controls but they need to be applied correctly for your safety and the best result.  An easier solution may be to just cover your plants temporarily with a physical barrier.  Lightweight spun fabrics (like Remay and others) are very good at protecting your plants from grasshopper damage.  A bait is available (Nosema locustae).  The bait needs to be applied in the spring as it is most effective on the nymphs, juvenile grasshoppers, that hatch in the spring.  The problem with the bait is that it needs to be applied to a large area.  If you live on a small city lot, it won't provide much protection as grasshoppers can move long distances.  For more information: 

http://cals.arizona.edu/yavapai/anr/hort/byg/archive/grasshoppercontrol.html

Codling Moths are fruit tree pests.  Adults lay their eggs on developing fruit blossoms.  The larvae hatch in 8 to 15 days, tunnel into the fruit and then tunnel out leaving behind their brown excrement.  Once they leave the fruit the fully-grown larva hides in the bark or litter on the ground and another cycle begins.  In Arizona there can be as many as three generations per year.  You can find them by looking at the fruit.  It will have small holes in it or the fruit will drop when it is still immature.  You can help control them by removing and destroying infected fruit and cleaning up debris around the tree.  There are chemical controls but they are not recommended for home growers because they kill bees and require multiple applications.  If you only have a few trees there are alternatives including pheromone traps and sticky bands.  Check the following link for more information:

ag.arizona.edu/yavapai/publications/yavcobulletins/Codling%20Moth.pdf

The damage from IPS Beetles and bark beetles is seen throughout the state.  Vast areas of trees are dead and dying.  The forests around Prescott are particularly hard hit.  There are several different species that infect different trees.  In pine forests you will find IPS Beetles and in cypress trees the Cypress Bark Beetle is the killers.  Infestations are becoming more common as the drought in Arizona has severely stressed the trees.  In pines, the needles start to yellow at the top.  Once you see the needles start to die, the tree is doomed.  On cypresses the branch tips start dying.  A cypress can survive the infestation unless it is stressed usually by drought.  If a cypress in your yard has been infected, you might improve its chances by watering.  The beetles can build up in piles of firewood and slash.  Piles of wood should be removed or covered with plastic and heated up but the plastic has to be completely sealed otherwise the beetles can escape.  There are no chemical treatments that do an effective job of controlling bark beetles.  For more information go to the Yavapai County Cooperative Extension Backyard Gardener columns, type in bark beetle for a series of articles.

http://ag.arizona.edu/yavapai/anr/hort/byg/index.html