How much nitrogen fertilizer do fine fescues need during establishment?

monc0003 — Fri, 29 Apr 2022 18:37:43 +0000

How much nitrogen fertilizer do fine fescues need during establishment? monc0003 Fri, 04/29/2022 - 13:37

Fri, 04/29/2022 - 13:37

By Ross Braun and Aaron Patton, Purdue University

A team of scientists at Purdue University, Oregon State University, and University of Minnesota investigated establishment differences among the fine fescue taxa and at the same time investigated the influences of different levels of nitrogen fertilizer and including clover. The objectives were to investigate differences among fine fescue taxa and determine optimal N fertility or clover-inclusion programs for fine fescue taxa during establishment for future low-input sites.

Figure 1. Fine fescue seedlings emerging in West Lafayette, Indiana. Photo by Ross Braun.

Figure 2. Six weeks after seeding at the experiment site in West Lafayette, Indiana in 2019. Photo by Ross Braun.

Five replicated field experiments were conducted (two in West Lafayette, IN, two in Corvallis, OR, and one in St. Paul, MN) between 2019 and 2021. All experiments were initiated at autumn seeding dates (late-August to early-October; Figure 1 and 2). Four fine fescue taxa (strong creeping red fescue, slender creeping red fescue, Chewings fescue, and hard fescue) were investigated. Eight nitrogen fertility and cover crop programs consisted of nitrogen fertilization levels ranging from nontreated (0 lb N 1000 ft⁻²) up to 2.5 lb N 1000 ft⁻²during the first two months after seeding. Also, two clover-inclusion treatments were included: no fertilizer with an annual clover cover crop or no fertilizer with a perennial clover companion cover crop at seeding. After seeding at each site, digital images were collected with a lighted camera box every 7 to 14 days until 70 to 90 days after planting, and grid counts and visual estimations of turf, clover, and weed cover were collected at 8 and 9 months.

Figure 3. Sigmoidal regression model results for the estimated number of days until 90% vegetation establishment of four turfgrass species across all five sites. Means followed by a common letter are not significantly different according to Fisher’s LSD (α < .05).

Results from all five locations showed that fine fescue taxa (i.e., turf species) had the biggest impact on establishment rate. The three F. rubra subspecies (strong creeping red fescue, slender creeping red fescue, and Chewings fescue) were similar to one another and required the shortest amount of time until 90% establishment compared to hard fescue (Figure 3). Results also indicated fine fescues should receive between 0.5 to 1.0 lb N 1000 ft⁻² during first two months after seeding and including clover in fine fescue seed mixtures can be successful but may slow establishment (Figure 4). Applying greater than 1.0 lb N 1000 ft⁻² during the first two months after seeding will not improve the rate of fine fescue establishment, unless a site has poor soil lacking organic matter. Overall, results indicate it may be beneficial to provide more N fertilization (0.5 to 1.0 lb N 1000 ft⁻²) during the first two months of establishment to promote a faster grow-in of fine fescue taxa at low-input sites and then N fertilizer levels can be reduced to a low fertility program (0.5 to 2.0 lb N 1000 ft⁻² yr⁻¹) in the long term.

Figure 4. Sigmoidal regression model results for the estimated number of days until 90% vegetation establishment of fertility and cover crop program treatments across all five sites. Total nitrogen fertility levels (lb N/M = lb N/1000 ft2) was the total amount of nitrogen applied using one to three applications during first two months after seeding. Means followed by a common letter are not significantly different according to Fisher’s LSD (α < .05).

The full manuscript of this experiment is open access (free) available in Crop Science journal (https://doi.org/10.1002/csc2.20704)

Reference

Braun, R. C., Braithwaite, E. T., Kowalewski, A. R., Watkins, E., Hollman, A. B., & Patton, A. J. (2022). Nitrogen fertilizer and clover-inclusion effects on the establishment of fine fescue taxa. Crop Science, 62, 947–957. https://doi.org/10.1002/csc2.20704