Like cotton aphids, whiteflies produce honeydew which accumulates on the leaves, and in dry environments can accumulate on the lint, causing sticky cotton. Fortunately in the Mid-South this honeydew is usually broken down by sooty mold fungi. Although this black sooty mold can accumulate on open lint and looks unsightly, it is actually beneficial because it destroys the honeydew, which would otherwise cause sticky lint. There is little evidence that sooty mold causes staining of lint, but it does cause concern to see heavy amounts of sooty mold on open bolls. Whiteflies normally lay their eggs on the undersides of leaves, where they are attached to the leaf by a short stalk that protrudes from the bottom of the egg and is inserted into the leaf.
Eggs can be extremely numerous, several hundred per square inch.
The eggs hatch into first instar nymphs, which are known as crawlers. Once these crawlers begin feeding and molt to the next instar, they become immobile and remain so for the remainder of the immature development stage. This means that this stage is not susceptible to control by either contact or systemic insecticides, and it is because of this stage, and the egg stage, that it is necessary to apply at least two applications at 5 day intervals when treating for whiteflies with most insecticides. Total development time from egg to adult takes approximately 20 to 25 days during the summer months. Adult whiteflies are fairly long lived.