Question
i have black ants on my 2 year old crabapple tree with allot of bumpy looking things on the bark and new growth are the ants protecting these things or eating them and how do i get rid of them ??

Answer
Sounds like a scale insect more than liley San Jose scale. One of the most important pests of the branches is the San Jose scale (Quadraspidiotus perniciosus). The adult scale insect is about 0.1 inch in diameter. It has a grey cover that hides the insects. Scale insects have thread-like mouthparts that are inserted into the bark. They feed on the sap. There are four generations a year in the South.

A single female scale can produce about 400 young over a six-week period. The young are called crawlers and move to a new area. They then settle down, insert their mouthparts, begin to feed and secrete the covering over their body. When populations are high, the crawlers may settle on the fruit. This produces a red measles-like spot on the ripe fruit.

Heavy scale infestations can kill individual branches. The best control for scale insects is a good application of dormant oil in the spring. This should be applied before the leaf buds begin to open. During the season, insecticide sprays will kill the crawlers.


They suck the plant juices from the twigs and sectret a substance called honeydew which is high in sugar content. This is what the ants are harvesting and they do protect the scales.

Some insecticides can be applied to the soil and taken up by the roots of the plants. These are called systemic insecticides. The most recent, Imidacloprid, is sold under the trade name Bayer Advanced Garden Tree & Shrub Killer Concentrate. (Merit is the trade name of imidacloprid used by professional tree care companies.) It is applied as a drench over the root zone. The tree takes the insecticide up and when the scale sucks the plant juices it is killed.