The most common problem of avocados in Texas is tip burn and marginal necrosis caused by water stress and salinity, which is most prevalent during hot, dry weather. This problem is most acute on Mexican-race seedlings and rootstocks; it can be tempered somewhat by more uniform and regular watering. Some avocados are prone to complete defoliation at the time of flowering. New leaves will develop almost immediately, so there is no cause for concern. The most serious disease of avocados is anthracnose, which is primarily a disease of fruit nearing maturity. It starts as circular, sunken brown to black spots that are quite small. With time, the spots can enlarge to half an inch or more and are prone to cause the fruit to crack horizontally and vertically across the spot. Anthracnose is particularly severe on thin-skinned types, but rarely causes significant losses on “Lula” and other thick-skinned fruits. Other fungal diseases such as cercospora spot, powdery mildew and scab are rarely encountered in Texas, but are serious problems in the humid tropics. Few insects have been documented on Texas avocados, although mites sometimes occur on the foliage. None has been severe enough to warrant control measures. Possums apparently thrive on mature avocado fruit and will climb the tree to feed in the absence of fruit on the ground.