   End of Summer Roundup - October 5, 2005 Jeff Schalau, County Director, Associate Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Following an abnormally wet winter, cool spring, and hot summer, fall is finally here again. It’s time to plant cool season crops, enjoy the cool weather, and stack firewood for winter. This week’s column will briefly review the summer growing season, discuss some current issues, and look at weather forecasts to see what might be in store. The winter moisture raised a bumper crop of cool season weeds that created favorable conditions for the beet leafhopper. This small insect is the vector of curly top virus (CTV): a disease that affects primarily tomatoes and pepper plants. Once infected, the plants stop growing and slowly die without producing. Many growers reported CTV and several of these replanted in June. The winter moisture also created very favorable conditions for small rodents (mice, woodrats, gophers, and rock squirrels). Many people had to aggressively control these species to reduce crop and landscape damage. On a positive note, the abundant winter moisture and average summer rains allowed local forests and rangelands to recover from previous year’s drought impacts. Cool season grass species, such as needle and thread grass and western wheatgrass, really grew well this year too. This produced early season forage for elk and cattle. Deer also appreciated the increased shrub growth that resulted in more abundant and nutritious browse forage. Summer precipitation was normal - whatever normal is for Arizona’s monsoon season. Our summer precipitation is so variable across the landscape. Overall, monsoonal precipitation was slightly below average in north central Arizona (50-75% of normal). However, the greater Flagstaff area received above normal monsoonal precipitation (125% of normal). As usual, some of the summer precipitation fell as hail in many areas of the county. This tends to cause crop damage where it occurs and falls as large hailstones. Late in the growing season, Cooperative Extension received many calls about tent caterpillars. Tent caterpillars are easily recognized by the webbed tents they create to give them protection from predators. They feed on buds and leaves of deciduous ornamentals and fruit trees. They are usually most active during the spring, but it seems they had a second generation this year. The literature says they are only supposed to have one generation per year, but these caterpillars obviously have not read the literature. On small trees and shrubs, hand removal through pruning or simply destroying the tent (webbing) can be very effective. A high pressure hose directed at the tents also disrupts them and can reduce damage considerably. Insecticides should only be used on high value trees where large portions are consumed. For more information about tent caterpillars, read the July 30, 2003 Backyard Gardener Column. According to the U.S. Drought Monitor, drought conditions improved considerably due to the wet fall/winter/spring of 2004-05 across much of Arizona. Areas in southeastern Arizona and western to central New Mexico are experiencing abnormally dry to moderate drought conditions. Lake Powell and Lake Mead are at 49 and 59 percent capacity respectively while the smaller Arizona reservoirs are close to or above their long-term average levels. Looking at forecasts, the NOAA Climate Prediction Center is calling for increased probabilities of above average temperatures and below average precipitation through the winter. The tropical Pacific Ocean is currently in a neutral El Nino Southern Oscillation (ENSO) pattern. This means that neither El Nino nor La Nina conditions currently dominate and there is an 80% or greater chance of these conditions continuing through February. Remember that La Nina conditions almost always cause below average precipitation in the southwestern U.S. and El Nino conditions often, but not always result in above average precipitation in the southwestern U.S. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. |