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Bridget McNassar, University of Idaho, mcna6910@vandals.uidaho.edu (Presenter)
Anthony Davis, University of Idaho, asdavis@uidaho.edu
Jeremiah R. Pinto, US Forest Service, Rocky Mtn Research Station, jpinto@fs.fed.us

 

Reforestation ventures have diverse objectives and involve myriad site characteristics, warranting stocktypes produced with these parameters in mind. Western larch and Douglas-fir seedlings were grown in containers of four volumes considered operationally feasible in the Inland Northwest (5, 8, 12 and 15 in3) in 2011. Sow date, irrigation and fertilization was customized for each species and container size in an attempt to produce the highest quality seedlings for each container size. This method produced seedlings that were generally larger in increased container volumes, but exhibited consistent shoot to root ratios and nitrogen percentages across all sizes of seedlings. Outplanting took place in the spring of 2012 in a series of replicated plots ranging from no to high weed competition. Seedling morphology, water status and gas exchange were measured throughout the growing season in an attempt to quantify the effects of container volume on seedling performance in different sites, as well as to hypothesize some of the physiological mechanisms for seedling performance. These results will help inform reforestation practitioners in choosing target seedling products for planting sites with various characteristics.