Potential of Increasing Canola Profitability through Canola-Triticale Mixtures in Dual Purpose Cropping of High Quality Forage and Canola Seed.

Winter canola (Brassica napus) is a cool season, rotational oilseed crop of particular interest for its healthful cooking oil and more recently the developing biodiesel market.  Winter canola originated from industrial oil rapeseed and produces large quantities of green, leafy forage prior to vernalization.  When grown for seed alone, canola can be less profitable than traditionally high valued crops such as corn and wheat.  In the dryland regions of the Pacific Northwest, winter canola crops often fail to establish because of dry soil conditions during planting in late summer and early fall.  Alternatively, soil moisture is often plentiful in spring and early summer and would greatly improve the dependability of winter canola establishment.  If winter canola is planted in early summer it would remain vegetative due to vernalization requirements and vegetative growth could be utilized for livestock feed in addition to seed production during the following summer.  Brassica forage crops are generally accepted as producing high quality feedstock for livestock and are typically high in energy, protein, and digestibility.  Canola crops establish quickly and have rapid regrowth capabilities; hence forage could be harvested within 8 to 10 weeks of planting, and with only 5 to 6 weeks between forage harvests.  After the final forage harvest the crop would be allowed to re-grow before the onset of winter, vernalize over winter and produce a seed crop the following summer.  In this system winter canola planted in early summer could provide an opportunity for dual-purpose (forage and seed) use with increased profitability.  Another forage crop commonly grown in the PNW is triticale which has shown consistent high forage yields.  However, triticale forage is higher in fiber and lower in protein than have been found in canola forage.  Despite high quality, one concern with spring sown winter canola is uneconomical forage yields under dryland.  Intercropping these two crops may provide an acceptable alternative.  Canola would compliment triticale by lowering fiber content and increasing crude protein of the overall forage, while intercropping triticale would boost yield.  After forage harvest, the spring-type triticale would either winterkill or be controlled with a grassy herbicide, leaving the winter canola to be harvested as a seed crop the following summer.  By intercropping spring triticale with winter canola, forage production is increased over a pure stand of winter canola.  In addition, canola forage has very little fiber content and can’t be harvest as hay or Haylage.  The purpose of this study is to evaluate forage biennial winter canola when intercropped with spring triticale.  Winter canola cultivar ‘Athena’ and spring triticale (x Triticosecale) cultivar ‘Trical 107’ were planted at right angles to one another.  Triticale was planted first at a depth of 2.5 cm using a 2.4 m planter, while the canola was planted second at a depth of 1.3 cm using a single cone, double disk small plot planter.  The experimental design was a 4 replicate split-strip plot design, where triticale planting rates were the main ‘strip’ effect followed by the ‘split’ canola planting rates.  Each crop was planted at 4 seeding rates.  Spring triticale was planted in 4.9 m wide strips at 0, 28.0, 56.0, and 84.1 kg ha^-1.  The winter canola was planted in 1.5 x 4.5 m wide rows at 0, 4.5, 9.0, and 13.5 kg ha^-1.  Once the triticale reached the late boot to the early heading phase of development (Feekes Stage 10.0 – 10.3), forage was harvested for an ‘early cut’.  Roughly 2-3 wks later the remaining plots were harvested while the triticale was fully headed and the kernels were in the milk stage (Feekes Stage 11.0-11.1).  Quality analysis was performed to observe the impact different seeding ratios had on quality of the overall harvested forage.   Highest forage yields were obtained from the triticale only treatment and lowers from the canola only treatment.  However several mixtures produced high forage yields of triticale and canola and which had markedly improved protein content yet sufficiently high fiber to allow harvest of Haylage.