In the North Thompson valley at the Lemieux Creek drainage, the initial results of a fertilization trial on Pseudotsuga menziesii (Douglas-fir) and Pinus contorta var latifolia (lodgepole pine) have been compiled. The study was established in the spring of 2003. Two hundred planted seedlings of each species in the trial were fertilized at the time of planting with teabag fertilizer; an additional two hundred seedlings of each species were identified as controls. One hundred of each of the fertilized and control seedlings, by species, were planted on the site in site prepared ground; the same density was planted on ground that had no site preparation. An additional two hundred Douglas-fir seedlings were fertilized at the nursery using a FAL product and equally divided between the site prepared and non-site-prepared ground. The purpose of the trial is to determine if fertilization at the time of planting, or at the nursery, will both increase seedling height and caliper and promote the achievement of minimum free-growing heights at an earlier date. Also being assessed is whether fertilization will result in the reduction or elimination of site preparation and, or brushing activities. The initial results of the trial indicate that both tree species present a moderate response to fertilization. However, height and caliper growth increases are not considered statistically significant at this time. Fertilized pine planted on non-site-prepared ground display a notable height growth increase of 8 percent, whereas fertilized Douglas-fir on the same ground display a height growth increase of only 1 percent when compared to their controls. In site preparation, fertilized pine increased its height by 4 percent, and Douglas-fir increased its height by 1 to 2 percent. Increases in caliper are more consistent between species where fertilized pine planted on plant 'as is' ground display a notable caliper growth increase of 6 percent, and fertilized Douglas-fir on the same ground display a caliper growth increase of 7 percent with teabag fertilization and 4 percent with FAL product fertilization. In site preparation caliper measurements showed the largest gains with fertilized pine being 9 percent larger than its control, and Douglas-fir being 4 percent larger with the FAL product fertilization technique. An additional component of the trial is to assess whether fertilization at the time of planting on plant 'as is' ground is more beneficial that planting unfertilized stock on site prepared ground. After one growing season, the heights and calipers of the seedlings, by species, planted 'as is' and fertilized with either product, were slightly larger than those without fertilizer and planted on site prepared ground. The results of Foliar Analysis indicate that fertilized trees of both of the species have increased levels of macro and micronutrients, over the control, with the trees fertilized at the time of planting showing the greatest gains. The stock that was fertilized at the nursery using the FAL product produced similar values to that of the control trees. As this trial is still in the very early stages, the results are not yet conclusive. Initial findings indicate that greater tree growth can be expected from fertilizer treatments over unfertilized trees. Results from future growing seasons are expected to confirm that fertilization at crop establishment results in more robust crop trees that are better suited to compete with vegetation and have the potential to achieve free-growing at an earlier date than would otherwise be expected. Also being monitored is how fertilization treatments on plant 'as is' ground compares to no fertilization on site prepared ground. Second Growth Consulting Ltd.
Second Growth Consulting Ltd.. 2004. Teabag fertilization at planting on Pseudotsuga menziesii, and Pinus contorta var latifolia: first growing season results - Lemieux Creek. Forest Investment Account (FIA) - Forest Science Program. Forest Investment Account Report. FIA2004MR121