Organic Winter Squash Systems Trial

Pest management, especially weed management, can be a challenge on organic farms. Practices that address one pest issue can have consequences for other types of pests. To explore the impact of weed management practices on squash yield and quality, insect and disease pests and beneficial insects, NYSIPM’s Abby Seaman, Bryan Brown and Marcus Lopez, along with Cornell AgriTech colleagues Chris Smart and Brian Nault, conducted a two-year trial to assess four production systems that could be used by organic farmers of various scales.

Trial

The trial compared the use of cultivation to several mulches—straw mulch, black plastic mulch and a roller-crimped rye cover crop. Seaman scouted for insects and diseases weekly throughout the growing season, which determined where to apply organic insecticides or fungicides. Half of the plots were left unsprayed to highlight the effects.

Findings

Weed biomass was minimal the first year in all treatments except in the roller crimped rye. There was a similar trend the second year, with the exception of the straw mulch system which had significantly less weed biomass than the cultivation system. Marketable yield was greatest in the plastic mulch and cultivation systems the first year and greatest in the plastic mulch the second year. The straw mulch tended to negatively impact yield and the roller crimped rye decimated yields. Marketable yield averaged 28% higher in the plots receiving insecticide and fungicide treatments.

Next Phase

The next phase of the trial will include an economic analysis of the systems, which had very different establishment costs. Since each of the systems, with the exception of roller-crimped rye resulted in good weed management and viable yields, it is likely that cost will reveal which system is the overall winner.