Bugs prepared for new missions at Palisade Insectary
Nearly 70 years after its inception, the Palisade Insectary is still looking for new challenges.
The insectary, which was started in the 1940s, collects, rears and distributes biological control agents such as predators, pathogens or parasites to feast on invasive pests and weeds in the Grand Valley and beyond. Its first project, raising parasitic wasps to kill the Oriental fruit moth that infested peach orchards since being inadvertently brought over from Japan in the 1920s, continues to this day.
More recently, it has targeted the tamarisk that have taken over the banks of rivers and streams throughout the Colorado Plateau. Its weapon of choice: the tamarisk leaf beetle, a natural predator of tamarisk in its native Eurasia.
The beetle happily has feasted on tamarisk foliage throughout Colorado and Utah, killing the trees and allowing native trees and grasses to move back in. The success has been strong enough that Dan Bean, the insectary’s director, is looking ahead to the next challenge.
“Conceivably, within five years we’ll move on from tamarisk beetles and hopefully onto the Russian knapweed gall fly,” he told a group of researchers and land managers touring the facility as part of the Tamarisk Coalition’s annual conference last week.
Russian knapweed, which can be toxic to grazing animals and kill surrounding vegetation, has been taking over grazing land in Wyoming and Colorado. A gall fly that stunts the weed’s growth and prevents it from spreading has shown promise as a control agent in Wyoming, and the Palisade Insectary has been rearing and releasing gall flies in Colorado. Bean said the insectary plans to increase its production of the gall fly five-fold in 2012 compared to 2011.
Even as new projects are expanded, though, their monitoring of tamarisk and tamarisk beetles will continue, just as their Oriental fruit moth project continues more than half a century later.
Multitasking seems to come second-nature to the facility. Currently, it releases and monitors about 20 different species of “biocontrols,” including 1,000 parasitic wasps per acre to peach growers in the Grand Valley.
In addition to Russian knapweed gall flies, the insectary is hoping to increase its production of a weevil that targets yellow toadflax, which resembles snapdragon and takes over higher-elevation grazing land.
Galls filled with overwintering weevil larvae are in storage at the insectary, ready to be warmed up and released in the summer. Eventually, Bean hopes to release biocontrol agents to target knapweed and toadflax throughout the state.
As one of only two state-sponsored insectaries west of the Mississippi, the biocontrols produced in Palisade can be shipped throughout the West and occasionally as far away as Massachusetts. Bean estimates about 20 percent of their shipments go out of state.
About 65 percent of the facility’s funding comes from the state of Colorado, while the rest comes from grants from the federal government, farmer co-ops, fees from the sale of biocontrols and gifts.
“I think it’s great that the state supports this kind of weed control. I feel fortunate that Colorado has taken such an interest,” the insectary’s Nina Louden told the tour.
Bean attributes Colorado’s interest in biological pest control to the insectary’s success taking on the Oriental fruit moth in the 1940s.
“That project worked well, so when other projects came along we already had the infrastructure,” Bean said. “We’ve been doing something that is important for weed management in the West, and we’re one of the only ones.”