Tree seedlings

Nepstad, D.C. Forest Regrowth inAbandoned Pastures of Eastern Amazonia Limitations to Tree Seedling Survival and Growth Dissertation Yale University New Haven, CT, 1989. 

G. Jentschke, D. L. Godbold, and A. Hiittermann, Culture of mycorrhizal tree seedlings under controlled conditions effects of nitrogen and aluminium. Physiol. Plant. 8l m (1991). 

In the first practical application of plant antifeedants for forest crop protection and wildlife management, snowshoe hare, L. americanus, fed less on coniferous tree seedlings after they had been sprayed with pinosylvin or pinosylvin methyl ether (Sullivan eta/., 1992). 

Crazier, E. R. (1991). Practical animal repellents for tree seedlings a success story. Forest Research Institute Bulletin 156,172-177. 

Certain tree species such as Betula pendula and Picea abies fail to develop in association with heather, Calluna vulgaris (40. 1). This apparently results from the production by heather of an allelochemical toxic to growth of mycorrhizae of Betula and Picea. Fruticose soil lichens are often allelopathic to the growth of mycorrhizae and forest tree seedlings also (42). Removal of reindeer moss (a lichen) in field tests resulted in accelerated growth of pine and spruce. 

Failures of newly established forest tree plantations or abnormal delays in tree seedling growth seldom have clear-cut causes. In the absence of knowledge of cause, foresters often attempt remedies that are unnecessarily costly or environmentally damaging, even when they succeed. Allelopathy, the direct or indirect deleterious effect of one plant upon another through the production of chemical inhibitors released into the environment, is likely a common cause of such failures or delays. 

Relatively little work has been done on allelopathic effects on VAM. Tobiessen and Werner (29) found reduced VAM formation in hardwood tree seedlings growing under pines, and spores of VAM fungi are absent from soil beneath living ponderosa pines, although they are abundant under dead trees ( ). Members of the nonmycorrhizal family Cruciferae sometimes inhibit VAM formation in associated plants though this doesn t always happen (31-3A). 

First spraying of first-year beds should be done just as a few tree seedlings begin to emerge, or earlier if weeds have germinated. There ter, no spraying should be done from the time germination is complete, until 4 or 5 weeks thereafter. 

Q. kelloggii tree seedlings grown under experimentally controlled daytime temperatures of 22 °C (low temperature treatment) or 27 °C (high temperature treatment) do not show a significant difference in either stomatal density or stomatal index (Table 4 Fig. 8). 

Lange, A.H. and J.C. Crane (1967). The phytotoxicity of several herbicides to deciduous fruit tree seedlings. J. Amer. Soc. Hortic. Sci., 90 47-55. 

Perez-Moreno, J. Read, D. J. (2000). Mobilization and transfer of nutrients from litter to tree seedlings via the vegetative mycelium of ectomycorrhizal plants. New Phytologist, 145, 301-9. 

Nepstad, D. C. 1989. Forest regrowth in abandoned pastures of eastern Amazonia limitations to tree seedlings survival and growth. Ph.D. Thesis, Yale University, New Haven. 

The authors had exposed grains, vegetables, brushes, and tree seedlings in pots to the fumes of an iron smelter at Biersdorf, Germany, at increasing distance from the source which is shown in plate 1. 

On the other hand, if the seedlings are transplanted into a recent clear-cut that was previously a forest dominated by the same or closely related species of trees (for example during post-harvest regeneration of the stand), they will generally do well. This happens because the clear-cut still has a population of mycorrhizal fungi that are suitable to inoculate the tree seedlings. 

Soil Nutrients and Tree Seedlings. In the germination experiment you could, for example ... 

Fay, D. A., and Mitchell, D. T. (1999). A preliminary study of the mycorrhizal associations of the tree seedlings growing on mine spoil at Avoca, Co. Wicklow. Biol, and Environ. Proc. R. Ir. Acad. 99B, 19-26. 

As for temperate plants, it is widely assumed that mycorrhizal associations in tropical forests serve to improve the uptake of mineral nutrients, particularly phosphorus (Bolan, 1991 Koide, 1991 Smith and Read, 1997). Growth stimulations and enhanced P uptake in response to mycorrhizal infection have been reported for tropical tree seedlings (Janos, 1989 Lovelock etai, 1996, 1997). 

Canswell, F. E., Grace, J., Lucas, M. E., and Jarvis, P. G. (2000). The interaction of nutrient limitation and elevated CO, on carbon assimilation of a ti(.)prical tree seedling (Cedrela odoraUi L.) Tree Physiol. 20, 000-000. 

Huante, P, Rincon, E., and Chapin, F. S. 111. (1995). Responses to phosphorus of contrasting successional tree-seedling species from the tropical deciduous forest of Mexico. Functional Ecol. 9, 760-766. 

Lovelock, C. E., Kyllo, D., Popp, M., Isopp, H., Virgo, A., and Winter, K. (1997). Symbiotic vcsicular-arbuscular mycorrhizac influence maximum rates of photos Tithe,sis in tropical tree seedlings girtwn under elevated CO,. Aust. /. Plant Physiol. 24, 185-194. 

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