Issue: July 28, 1997

Apple leaves drying up

The leaves on my apple tree are turning brown, curling, and some are drying out. A sample is inclosed. I spray regularly with Diazinon(TM). Can you tell me what is wrong and what I should be doing?

The leaves you sent were infested with spider mites. Although they were present in large quantities, the webbing which they often produce was not especially evident. It was the mites themselves that I saw through my hand lens. You would not be able to see them easily without some magnification.

Mites are small arachnids, not insects, and are not controlled by all insecticides. The Diazinon(TM) you are spraying is probably for codling moth control. It is not going to control the mites. A word of caution - Sevin(TM) insecticide which is used by some apple growers may increase spider mite damage to the trees.

You may wish to use strong jets of water to disrupt the spider mites, washing many from the tree and others from their feeding site. It also destroys the fine webbing which protects the mites from our low humidity and natural predators. If washing well with water does not reduce the problem, there are miticides labeled for control of spider mites on apple. Use miticides in accordance with their label directions taking special notice of the interval you must wait between the last application and harvest.

Wildlife garden

I have heard of something called wildlife gardening. What is that? It sounds interesting.

Wildlife gardening means gardening in a manner which encourages wild animals to visit your garden. Just which wild animals you are inviting depends in large part on what you are growing and the manner in which you grow it. Most people in cities are interested in increasing the number of birds when they think of wildlife gardens. Some may actually wish to encourage deer and other larger mammals to visit their garden, though most gardeners prefer not to suffer the damage these larger animals inflict. Some gardeners want their garden to encourage beneficial insects. Others just want a native landscape which all native wildlife will visit.

Some of the wildlife, such as deer, can be a problem for traditional gardens. Others such as rock squirrels and other rodents, especially deer mice, can be health hazards for the gardener, his family, and friends. Finally, while they will reduce rodent problems, snakes are not always welcome visitors in gardens, especially the venomous snakes. Some people are willing to allow even venomous snakes into the garden.

So, which do you wish to invite into your garden? Choose plants which provide the preferred food for your desired guest. Hummingbirds like red flowers, but will visit most flowers which produce nectar. Other birds will need their favorite food, cherries perhaps, or sunflowers, amaranth, and other dry seed producers. Water also invites birds into the garden, especially here in the dry environment of New Mexico. Birds and other small animals need nesting sites and cover which protects them from predators. Shrubs, tall grasses, and trees provide this habitat. Be sure to choose plants which will also provide beauty and food for you if you wish.

A wildlife garden may provide many hours of enjoyable animal watching, but you must be prepared to observe nature at work in your wildlife garden. When rodents, snakes, and birds increase in numbers they become attractive to predators which feed on them. My neighbor has set up bird feeders and successfully attracted many birds. We now have a sparrow hawk which frequents the power lines. In forested areas and open spaces, larger raptors such as owls and other hawks may appear. They will feed on some of the animals invited to your wildlife garden. This is the way the system works and to be expected in the wildlife garden.

Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms and the NMSU Horticulture Publications page.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!