Legislation to reduce open field burning in grass seed fields within the Willamette
valley of western Oregon changed established production practices. In the creeping
grasses such as Kentucky bluegrass (Poa pratensis L.) and creeping red fescue (Festuca
rubra L.) non-thermal management resulted in reduced yield.
Studies were conducted to examine the effects of three stubble height treatments in
comparison to open field burning in creeping red fescue seed production. The effects of
light quality on characteristics of plant development were investigated in field and
controlled environments. Exogenous applications of plant growth regulators (PGR's)
were made to elucidate the causes of low seed yields observed without burning.
Field plots were prepared in fall of 1994, and 1995 in creeping red fescue
commercial production fields as well as at Hyslop research farm in 1995. Three cultivars
were included in the trial; Shademaster and Hector, which produce many rhizomes, and
Seabreeze which produces few rhizomes. The effects of stubble height, PGRs, and field
burning were measured during fall regrowth and flowering. Non-structural carbohydrates available for early regrowth were reduced when stubble was removed below 5.0 cm,
particularly in first-year stands. Fall tiller height was increased by stubble remaining and
was negatively correlated with flowering. Rhizome development was reduced when
stubble was removed mechanically or burned to the crown, whereas yield potential was
increased.
Fall ethylene application reduced fall tiller height, fall tiller number, and percent
fertile tillers the following spring and was similar to control treatment compared with
burn. Other PGRs did not produce consistent results in this study. Excess ethylene
produced by decaying stubble may impact floral induction and reduce yield potential in
creeping red fescue seed crops.
Light quality as measured by red:far-red ratio (R:FR) was reduced by canopy
closure during regrowth but not by the presence of stubble. In controlled environment
studies, red light (R) promoted taller tillers, greater stage of development, and greater
tiller number than far-red (FR) light. Sunlight enriched with FR completely inhibited
rhizome formation. Results suggest that environments with excess reflected FR may
negatively impact early development of creeping red fescue seed crops. / Graduation date: 1998
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/33990 |
| Date | 29 September 1997 |
| Creators | Meints, Paul David |
| Contributors | Chastain, Thomas G. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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