Cereal leaf beetle

Cereal leaf beetle in Oregon

The cereal leaf beetle (Oulema melanopus), normally a pest of agricultural crops such as barley, oats and corn, has reportedly been spotted feeding on Calamagrostis at an Oregon nursery in the Willamette Valley. Positive verification is pending. Native to Europe and Asia, the species was first confirmed in Michigan in 1962 and has since spread throughout the U.S, extending its reach to at least 30 states. Both larvae and adults feed on leaves; most damage is caused by larvae stripping foliage of chlorophyll. Such aesthetic damage can dramatically affect economic value.

Thousands of acres of trees in the Rockies have been decimated by the mountain pine beetle.

Mountain pine beetle goes to town

Mountain pine beetle (Dendroctonus ponderosae) is moving into Colorado’s Front Range cities, but foresters and arborists are optimistic about the fate of the urban trees, because well-irrigated pines in managed landscapes appear to fare better than their drought-affected relatives in the uplands. The pest has killed millions of trees in Colorado and throughout the Rocky Mountain states, favoring ponderosa, lodgepole, Scotch and limber pines. The cause of the urban invasion appears to be transportation of infested firewood. Fewer than 100 trees in Denver city parks have been affected; crews have removed 10 that died.

Thousand cankers disease has been confirmed in Bucks County, Penn.

TCD detected in Pennsylvania

Thousand cankers disease has been confirmed for the first time in Pennsylvania; a black walnut in Plumstead Township, Bucks County, was affected. A quarantine has been implemented, restricting the movement of all walnut material including nursery stock, budwood, scionwood, green lumber and firewood. It also covers other walnut material – living, dead, cut or fallen – including stumps, roots, branches, mulch and composted and uncomposted chips. Due to the difficulty in distinguishing between species of hardwood firewood, all hardwood firewood is considered quarantined. The quarantine also restricts the movement of walnut material and hardwood firewood from states known to have TCD, including Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oregon, Tennessee, Utah, Virginia and Washington.

Passionvine mealybug enjoys the hospitality of more than 250 species of plants.

Passionvine mealybug hits Florida

Stating it was “only a matter of time” before the Caribbean pest hit the U.S., USDA-APHIS officials have confirmed the presence of Planococcus minor (passionvine mealybug) at the Fairchild Botanical Gardens in Miami. The scale is nearly indistinguishable from its relative, P. citri (citrus mealybug). The host list for the pest is extensive, exceeding 250 species in 80 families and including agricultural and horticultural plants alike. Predators and parasitoids are not known to exist in Florida; however, natural enemies of citrus mealybug are expected to find P. minor to be suitable hosts or prey.

Red palm weevil (above) and American palm weevil (below) have been detected in southern California, leading specialists to speculate as to what their combined damage could mean to the state’s palm population.

Could California experience “Palmageddon”?

Two species of giant palm weevils have the potential to wreak havoc on the state’s iconic palm trees should they combine forces, according to Mark Hoddle of the Center for Invasive Species Research. Rhynchophorus ferrugineus (red palm weevil; RPW), a category-1 pest of date palms in the Middle East, and Rhynchophorus palmarum (American or South American palm weevil; SAPW) both have been detected in southern California. In addition to its own destructive powers, R. palmarum vectors a nematode (Rhadinaphelenchus cocophilus) that causes red-ring disease of coconut. Breeding populations have not yet been confirmed, but Hoddle speculates, “Potentially, for the first time, an extraordinary invasion scenario may be unfolding in Southern California with respect to exotic palms and invasive palm weevils.” He continues, “So what could this mean for the palms of Southern California? This is obviously difficult to answer, but one potential concern could be the ability of RPW to acquire from SAPW the red-ring disease nematode and spread it as well. If this happens, it may increase the vector capacity for this nematode as two weevil species instead of one could spread the nematode to susceptible palms. This could cause a severe disease epidemic for California’s palms.” For more, read Hoddle’s blog at http://cisr.ucr.edu/blog.