Christmas tree pests and weeds required restrictions and requirements to be placed upon Christmas tree growers with plantations in "gypsy moth regulated areas". The restrictions and requirements included ongoing site monitoring, active moth eradication by the grower, accurate record keeping, and government directed moth eradication programs. Failure to abide by the rules could result in revocation of the "approved grower" status from the Canadian Food Inspection Agency. The major types of conifers cultivated, pines, Douglas-firs, true firs, and spruce trees, are all affected by some types of insect pests. Douglas-firs are most vulnerable to the Cooley spruce gall adelgid. The true firs are most susceptible
Medium tree finch same. This reflects the fact that the two species feed on the same type and size of insect. The beak of the medium tree finch is intermediate in size between the small tree finch and large tree finch. All three species are found in the same habitat. The medium tree finch is threatened by introduced predators such as rats, mice, cats, and the smooth-billed ani, as well as habitat loss, which has occurred through clearance for agriculture. The introduced fly "Philornis downsi" is a significant threat to the survival of this species. Parasitic larvae of this fly live in the