Christmas tree farms from North Carolina to Massachusetts struggle with managing armored scale pests. These insects cause yellow spots to form on needles where feeding occurs, and can even cause partial defoliation of trees. The effectiveness of systemic insecticides is declining on some farms, which may indicate that insecticide resistance has occurred. However, the scale populations on some farms appear to be held to non-damaging population levels through the action of natural enemies. This project will establish flowering vegetation as an intercrop in row middles on a Christmas tree farm to simultaneously help support beneficial insects, and to provide an additional revenue stream through honey production. Unlike perennial fruit crops that are highly dependent on foliar applications of insecticides to protect crops, Christmas trees can be grown without application of insecticides that would be hazardous to pollinators. We will test whether ground covers can be established and maintained within a Christmas tree farm to provide multiple benefits: floral resources to support honey bees and natural enemies of armored scales (the most damaging insect pest of true firs), and reduce labor and machine hours to maintain the groundcover.
Project objectives from proposal:
(1) This project seeks to establish intercrops of honey plants within a Christmas tree planting.
(2) This project seeks to measure inputs required for establishing and maintaining these intercrops. Inputs will include cost of seed and any herbicides used to favor the establishment or to maintain the intercrop.
(3) This project seeks to measure the honey bee activity within the different intercrops over a growing season: this will serve as a surrogate for measuring honey yield from specific intercrops being tested, because honey bees can forage for several miles from their hives and cannot be caged on these crops to measure honey yield.
The information gained will permit other growers to establish plantings most compatible with their specific objectives (e.g., bee forage and honey income, support for natural enemies of insect pests, fixing of nitrogen, and/or reduction of vegetation management costs).