Here’s a new article from our seed production research and extension team on frequency and seasonal timing of irrigation and its effects on seed yield and yield components in perennial ryegrass (Lolium perenne L.) seed crops.  Field trials were conducted in the Willamette Valley over a 5-year period at OSU’s Hyslop Farm.

Irrigation system (TG Chastain photo)
Irrigation system (TG Chastain photo)

This article will appear in an upcoming issue of Field Crops Research.

Key findings of the article:

• Spring irrigation increased seed yield of perennial ryegrass but fall irrigation did not.
• Most perennial ryegrass cultivars tested responded to spring irrigation with increased seed yield.
• Seed yield increases attributable to spring irrigation resulted from increased seed number and seed weight.
• Seed yield was not substantially affected by the expression of other seed yield components.

The article can be found at the link below:

Chastain, T.G., C.M. King, W.C. Young III, C.J. Garbacik, and D.J. Wysocki. 2015. Irrigation frequency and seasonal timing effects on perennial ryegrass (Lolium perenne) seed production. Field Crops Research 180:126-134.


Thomas G. Chastain

The combination of very dry and warm weather in spring and early summer 2015 is a cause for concern for growers of grass and forage legume seed crops in the Willamette Valley. Moreover, these conditions have accelerated the timing of the harvest of seed crops in the region. One question that has arisen is how will these conditions affect seed yield?

Seed Field
Aerial view of windrow-harvested seed field in the Willamette Valley.
Continue reading

Bill Young, OSU professor emeritus and extension agronomist in seed production, has recently updated Oregon’s grass and forage legume seed crop production estimates for the 2014 crop year.  This information was gathered by OSU Extension crops agents working in Oregon’s seed production regions and Nicole Anderson, an OSU Extension Field Crops Agronomist, played a key role in coordinating this effort.

This report provides a wealth of useful information about quantity of seed produced, crop yields, and economic value of seed crops in Oregon.

Here is a summary of key findings in Dr. Young’s report:

In brief, the combined value for all grass and legume seed crops in the 2013-14 crop year ($510,880,000) increased by 10.6% over the value of production in 2012-13 ($461,693,000) to mark a new record high over the $505,309,000 value set back in the 2007-08 crop year. The value of grass seed sales increased 7.5% ($31,392,000) over last year, and legume seed crops forged ahead 40.4% over last year’s record sales of $44,067,000 to a new high of $61,862,000. Acres of grass seed crops increases only 0.6% (2,634 acres) while total poundage surged by 10.8% (71,287,000 pounds). Legume seed crop acreage increased by 7.8% (3,142 acres) while total production jumped 16.4% (4,601,000 pounds).

Here is a link to the report on OSU’s Seed Crops page:

2014 Grass and Legume Seed Crop Estimates

You can follow the links on the Seed Crops page to find information about this past year’s seed crops and comparisons to previous crop years. Historical reports are also archived at this page.


Thomas G. Chastain

In order to maximize harvest efficiency and seed yield, using the appropriate timing for harvest is essential. Seed moisture content is the most reliable indicator of seed maturity and harvest timing in grass seed crops.

Since pollination and seed maturation are not uniform processes in grass seed crops, a range of seed maturity can be found in a single field. Harvesting within the correct range of seed moisture contents will maximize seed yield and minimize losses of seed during harvest. Seed moisture content is also an important factor in the storage of harvested seed. High seed moisture content reduces longevity of seed in storage and reduces seed quality. Continue reading

That’s the word from Dr. Anthony Montanaro at Oregon Health & Science University in a story published in the Oregonian:

It’s a miserable time for allergy sufferers in Oregon

There’s no question that the flowering of grasses began earlier this spring season in the Willamette Valley as a result of warm weather conditions and that has led to earlier shedding of pollen in the area’s grass seed fields.  However, there is no evidence at this time to indicate that grass pollen and associated problems for allergy sufferers will be headed to a later ending as the article suggests.  In fact, the dryness of the season and warm temperatures strongly support the notion that the grass pollen season will conclude sooner rather than later this year as the crops are already starting to be harvested now.

The present evidence based on the flowering progress of grass seed crops and conditions in the seed fields suggests an early end to the pollen season, not a later end.

Strong creeping red fescue in flower (T.G. Chastain photo)
Strong creeping red fescue in flower (T.G. Chastain photo)


OSU is presenting two seed production field days in May where the public can visit research farms and learn more about research activities. The field days provide a convenient choice for those located in either the western or eastern parts of the state.

May 19 – Grass Seed Field Day – Various topics focused on grass seed production practices and pests including ergot, powdery mildew and weed control, climate change, and more. Starts at 8:30 AM and ends at noon.

Located at OSU’s Hermiston Agricultural Research and Extension Center, 2121 S. First Street, Hermiston, OR 97838. Phone (541) 567-6337.

May 27 – Hyslop Farm Field Day – Plant growth regulators, nutrient and irrigation management in clover seed crops, weed management in grass seed crops, biological control agents for clover root borer, canola, wheat, barley, and more. Starts at 8:15 AM and ends with lunch provided by the OSU Crops Club.

Located at Hyslop Crop Science Field Research Laboratory just off Highway 20 between Corvallis and Albany at 3455 NE Granger Corvallis, OR 97330. Phone (541) 737-6067. Hyslop Farm location