Juniper trees, sometimes referred to as large shrubs, are sturdy ornamental plants well-suited for use in the garden or grown in containers. Though they often withstand poor and varied conditions, juniper trees are susceptible to pest infestations that result in minor to severe damage. Familiarize yourself with how to identify a juniper tree mite problem as well as control methods to keep your junipers healthy.
Maintain vigorous trees through proper care as a preventive method to keep pests away. Pests such as mites prefer weakened plants for invasion. Thriving in full sunlight, juniper trees need well-drained soil for healthy growth, according to the Clemson University Extension. These trees are tolerant to drought and high temperatures but quickly fall ill in waterlogged soil and may suffer injury from heavy pruning.
Spruce spider mites (Oligonychus ununguis) are not true insects. As their name suggests, this bug species is more of a spider in nature. Causing widespread infestations on juniper trees, these mites are difficult to identify due to their small size. For identification, place a light colored cloth or paper beneath a tree branch and give it a tap; if a mite infestation has taken hold of your juniper, mites will fall from the branch where their presence is made visible on the lighter material, according to the Clemson University Extension.
Symptoms and Damage
Spider mites are "sucking" bugs, which means they insert their mouths into plant tissue to suck fluids. Symptoms include tiny yellow specks or dots on needle surfaces as well as browning of foliage and defoliation, according to the Clemson University Extension. Also look for a weblike formation on plants as a sign of infestation. Severe infestation for more than one year in a row may result in plant death.
For natural control of juniper tree mites, release predatory, natural enemies into the garden. These insects hunt and kill pests without causing further damage to your juniper trees. Find natural predators in garden supply catalogs and stores. Natural enemies of the spruce spider mite include ladybugs, also referred to as ladybird beetles. Additionally, spray your juniper tree with a strong stream of water to knock mites from plant surfaces, according to the Clemson University Extension.
When you check for mites with the cloth or paper test, a significant amount of mites means your tree is severely infested. Before turning to chemical treatment, check the tree every week for several weeks to determine whether or not the problem is tapering off, particularly if you have released predatory insects. If the infestation is severe, apply an insecticidal soap for use on junipers as a treatment for spruce spider mites. Another option is the application of a pesticide including the active ingredients fenbutin oxide and acephate, according to the Clemson University Extension. When in doubt, contact a professional or your county extension agent for safe pesticide application.