Tree Seedlings on Logs in Picea‐Tsuga Forests of Oregon and Washington
- 1 February 1989
- Vol. 70 (1), 48-59
- https://doi.org/10.2307/1938411
Abstract
Logs are the major seedbed for trees in coastal Picea sitchensis–Tsuga heterophylla forests. Field experiments were conducted at Cascade Head, Oregon, and Hoh River, Washington, to examine pathogens, predation, competition, and standing water as causes for this close seedling–log association. More seedlings survived on log blocks than on soil blocks, regardless of whether the blocks were raised or placed flush with the soil surface. Standing water was therefore an unlikely cause of the seedling–log association. Comparisons of plots protected from and exposed to predation revealed that predation was minor and of equal intensity on soils and logs. Sterilizing soils did not consistently increase seedling survival above controls. Clearing ground–layer vegetation from soil plots significantly increased the survival of conifer seedlings compared with that on uncleared soils. The seed penetration rates through moss mats indicated that <1% of the seedlings germinated within moss mats. Competition with herbs and mosses on the forest floor therefore appears to be responsible for the disproportionate number of tree seedlings found on logs. Recently fallen logs represent sites where competition is low enough for tree seedling recruitment within many Picea–Tsuga forests.This publication has 16 references indexed in Scilit:
- Factors influencing understory seedling establishment of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in southeast WyomingCanadian Journal of Botany, 1982
- Mass, nutrient content, and decay rate of dead boles in rain forests of Olympic National ParkCanadian Journal of Forest Research, 1982
- Gap Regeneration in Some Old‐growth Forests of the Eastern United StatesEcology, 1981
- Effects of Tree Leaf Litter on Herbaceous Vegetation in Deciduous Woodland: I. Field InvestigationsJournal of Ecology, 1981
- The role of mosaic phenomena in natural communitiesTheoretical Population Biology, 1977
- Resource Division in an Understory Herb Community: Responses to Temporal and Microtopographic GradientsThe American Naturalist, 1976
- Conifer Seed Survival in a Western Oregon ClearcutEcology, 1967
- Decline of Old‐Growth Redwood Forests in Relation to Some Soil Microbiological ProcessesEcology, 1965
- The Relationship of Fungi to Survival of Shaded Tree SeedlingsEcology, 1962
- A Study of Some of the Factors Affecting the Natural Regeneration of Tamarack (Larix Laricina) in MinnesotaEcology, 1954