Growing degree days (GDD) are commonly used to schedule the beginning of spring nitrogen fertilizer applications in grass seed crops. Typically, 200 GDD (base 0 C) from January 1st is used as the opening date of spring nitrogen fertilizer applications. This number of GDD marks the beginning of the period that the average daily temperature reaches 5 C (41 F) and as a result, grass seed crops resume growth after winter quiescence.
The current (February 13th) GDD is 197 GDD at Hyslop Farm near Corvallis. At the current rate of GDD accumulation, 200 GDD should be attained on the 14th. The long-term average date for attaining 200 GDD is February 14th.
Here’s an article just published by our seed production team on nitrogen’s effect on seed yield and other seed production characteristics in yellow mustard. Trials were conducted on this crop over a 3-year period at OSU’s Hyslop Farm by Alyssa DuVal, a former graduate student and current instructor in the department. Yellow mustard is a potential seed crop for the high rainfall areas of western Oregon and unlike many other Brassica family crops, there is no threat of crossing of yellow mustard with the region’s vegetable seed crops.
This article was published in Agronomy Journal and can be found at the link below:
Here’s a new article from our seed production research and extension team on spring nitrogen and seed yield in winter canola. Field trials were conducted in the Willamette Valley over a 3-year period at OSU’s Hyslop Farm. This work was led by Brock Ferguson and is the first study to be published on winter canola in the seasonally wet environment of western Oregon.
This article appears in the most recent issue of Agronomy Journal and can be found at the link below:
A new nutrient management guide for tall fescue seed crops has been published by OSU’s seed production research and extension team. The 42-page publication (EM 9099) is a product of many years of field work in tall fescue seed crops by the members of the research and extension team.
The nutrient management guide covers the impacts of application of nutrients on seed yield, seed yield components, crop growth and development, plant growth regulator use, pests, and others. Extensive use of tables, figures, and appendices supplement this comprehensive guide to tall fescue seed crop nutrient management.
The publication can be accessed at the link below:
Here’s a new article from our research group on the impacts of spring applied nitrogen and trinexapac-ethyl plant growth regulator (PGR) effects in perennial ryegrass and tall fescue seed crops. This article is in the current issue of Agronomy Journal and is a part of our series on PGR in grass and legume seed production. The product is marketed as Palisade, Moddus, and several generic products for lodging control in grass seed crops and legume seed crops.
Key findings of the article:
Identifies an interaction of spring-applied N and PGR application on seed yield and other seed production characteristics in perennial ryegrass and tall fescue.
Is the first peer-reviewed publication to document the effect of trinexapac-ethyl PGR on increasing seed yield in tall fescue.
Seed yield was only increased in perennial ryegrass and tall fescue by the PGR when recommended rates of applied rates of spring N were made.
Although seed weight was increased by spring N, most of the effect of the combination of spring-applied N and PGR on increasing seed yield was attributable to increases in seed number.