Q. Perhaps you can tell me why in Odessa, Texas, fruitless plum trees are actually fruitless and don’t fall easy prey to borers. A.  Ornamental plums, we sometimes call purple leaf plums, are actually fruit bearing trees (fruit trees) that are sold for landscaping because of their showy flowers. They are from a group of fruit trees collectively called “cherry plums”. Actually, some cherry plums have purple foliage and some have green.             Two popular purple varieties are ‘Thundercloud’ and ‘Atropurpurea’. Cherry plums require a pollenizer (another tree similar but distinctly different) to set fruit. If no pollenizer is nearby, then there is little to no fruit. Purple leaf Plum flowering             Some cherry plums will set a only few fruit by themselves but many more fruit if a pollenizer tree is closeby. If there is a pollenizer nearby, you might see a lot of fruit produced.             Fruit set without a pollenizer can depend on the climate as well. Late frosts after flowering can cause any fruit that might set, to fail.             The types of borers present vary with the climate and geographical location. Also, borers are transported inside nursery plants between states. This is one method they have for getting around…by truck! A very good indication that this purple leaf Plum has borers working inside the trunk             If a state like Nevada is dominated with nursery plants grown in California, these plants are much more likely to have pests common to California. If plants are bought from nurseries in Texas (Texas has a booming nursery industry) then the pests are more likely to be pests common to Texas.             Borers are decomposers. They are attracted to plants that are weakened or damaged. Our intense sunlight is tough on plants and can weaken them. Our soils are poor and can lead to unhealthy plants as well. These all make a nice hunting ground for borers.