Predators

Birds and small mammals feed on mature cones and seeds. The largest losses are probably from squirrels, but birds and other small mammals can cause havoc to a cone crop. Squirrels cache cones from western conifers and later feed on the whole closed cones. The Clark’s nutcracker can be very efficient at gathering cones just before the seed is ripe. Nutcrackers extract seeds from closed and open cones, caching the seeds where they can find them later. Although some reports state that nutcrackers will cache the cones of a variety of conifer species, they are notorious for caching whitebark pine seeds, wiping out a complete crop if the cones are not protected.

Predation usually is not a significant problem during years when cone collections are planned, because an abundance of cones should be available. Some techniques can be used to protect important cone crops.

Whitebark pine cones have been protected by placing wire cages over the cones during the summer season. <provide pictures of cages, constructing cages, installing cages> When trees are close to roads or on ground that is easily accessed, cages can be installed from lift trucks or cherry pickers. In less accessible areas, climbers probably will have to install cages on trees. If you are working with whitebark pines, rely on the help of other districts that have experience protecting the cones.