Effects of Boron Fertilizer on Alfalfa Yield and Quality

Objective:                   

To evaluate the effects of boron fertilizer rate and timing on alfalfa yield and quality.

Summary:       

Boron treatments were applied to evaluate the impact on alfalfa yield and quality, which included 5 rates of 0, 0.25, 0.5, 1, and 2 lbs/A at begin season (April 16) and 4 rates of 0, 0.25, 0.5, and 1 lbs/A at midseason (June 23). The experimental design was a randomized complete block with five treatments and four replications. Treatments were applied when the crop averaged 2-3 inches in height. There was a full soil profile beginning of green up in spring as rainfall received in the fall and early spring was above average. From the first green up to the last cutting (April to September, 2015) only 3.5 inches of rain was received and supplemental irrigation was needed. Height measurements were taken prior to cutting when plants averaged 10% flowering. Three cuttings were made.

No significant differences were observed for height or yield (Table 2). Average total yields were 6.1 T/A. First harvest had the highest yield at 3 T/A while third had the lowest at 1.4 T/A.  The initial soil test for Boron in spring was low, but the average Boron tissue test (Table 3) were near or at sufficiency level for low Boron application, thus, no consistent hay quality trend can be observed. Alfalfa Boron trial was conducted on the second year of alfalfa establishment. Future studies will consider irrigation as an additional factor to Boron uptake and hay quality.