REPRODUCTIVE DEVELOPMENT AND INSECT DAMAGE ON WHITE AND BLACK SPRUCE SEED TREES TREATED WITH AMMONIUM-NITRATE AND CARBOFURAN

Citation
Wh. Fogal et al., REPRODUCTIVE DEVELOPMENT AND INSECT DAMAGE ON WHITE AND BLACK SPRUCE SEED TREES TREATED WITH AMMONIUM-NITRATE AND CARBOFURAN, Canadian journal of forest research, 23(9), 1993, pp. 1786-1792
Citations number
50
Categorie Soggetti
Forestry
ISSN journal
00455067
Volume
23
Issue
9
Year of publication
1993
Pages
1786 - 1792
Database
ISI
SICI code
0045-5067(1993)23:9<1786:RDAIDO>2.0.ZU;2-C
Abstract
Granular ammonium nitrate and carbofuran were applied to soil beneath white spruce (Picea glauca (Moench) Voss) and black spruce (Picea mari ana (Mill.) B.S.P.) seed trees to stimulate reproductive development a nd protect them from defoliating and cone-feeding insects. Rates of ca rbofuran application were 0, 10.8, or 21.6 g/cm DBH for white spruce, and 0, 5, or 10 g/cm DBH for black spruce. Both species received 0, 22 4, or 448 kg N/ha of ammonium nitrate. Trees were assessed for defolia tion by the eastern spruce budworm (Choristoneura fumiferana Clem.), c one insect damage, seed-cone bud production, cone production, seed yie lds, and needle senescence for 3 years in white spruce, and 2 years in black spruce. On white spruce, carbofuran reduced defoliation and num ber of spruce budworm at both application rates in the year of treatme nt and at the, high rate in the second year; no protection was observe d in the third year. Seed-cone bud production was stimulated by carbof uran for 3 years following treatment. Needle senescence was increased by carbofuran. Ammonium nitrate decreased needle senescence but had no effects on other assessment variables. On black spruce, carbofuran di d not reduce spruce budworm numbers or protect cones in the year of ap plication but, in the year after treatment, both foliage and cones wer e protected. Defoliation was reduced by the low rate of applied ammoni um nitrate. Treatments did not influence the number of seed-cone buds or cones or amount of needle senescence in black spruce.