Boxwood Leafminer are small flies that attack several varieties of boxwood, causing the usually dense foliage to appear weak and lackluster. These pests can kill boxwood twigs and cause mature plants to become susceptible to other diseases, including winter-kill in colder climates.
There are multiple rust fungi that affect cedars (junipers): cedar-quince rust, cedar-hawthorn rust and cedar-apple rust. All of these rusts require two different hosts and alternate between them during the year. Cedar-quince rust appears as elongated branch swellings that produce orange spores.
Eriophyid mites are the smallest arthropod pests on plants. Two common eriophyid mites are ash flower gall mite (Eriophyes fraxiniflora) and pine bud mite/needle sheath mite (Trisetacus pini). Because the mites have relatively short mouthparts, they feed on cells just under the plant surface and may cause galls, witches broom and browning or yellowing of leaves or needles.