It’s the start of new semester. Best way to get student’s attention is with a pop quiz right off the bat! So in that vein, we’ll cross things up and give a quiz on Monday instead Friday. Relax; to make things a little easier we’ll make this one a matching exercise.
Here goes. At our recent Christmas tree conference in Austria, a colleague of mine at Oregon State University, Chal Landgren, presented the results of a study to look at the effectiveness of foliar fertilization on Nordmann fir. Trees were grown in 15 gallon containers and assigned to one of four groups:
1) control: no fertilizer
2) soil applied controlled release fertilizer
3) foliar nitrogen fertilizer
4) soil applied fertilizer + foliar feed
Since Chal has yet to publish this I need to be a little careful with details but all fertilizers were commercially available products labeled and marketed for this purpose and were applied at manufacturers’ suggested rates and intervals.
At the end of the growing season, the trees were sampled for needle nitrogen content. As a point of reference a needle nitrogen content of 1.5 – 1.6 % is usually deemed adequate for this species.
For your quiz: match the treatments listed above to the nitrogen concentrations below:
Answer and discussion tomorrow…