Dry-Farm Trials at Valley Flora
Drought has been in the news aplenty the past few years, with growing concerns about implications for agriculture in Oregon. A quick glance to our south doesn't paint a pretty picture of what could be in store for us. In drought-plagued California water wars have been raging fierce as the state grapples to balance the demands of urban centers, native salmon runs, and farm production. At the peak of water shortages a couple years ago, almost 2 million acres of prime farmland in the Central Valley - which produces almost half of the nation's fresh fruit and vegetables - were left fallow for lack of irrigation water. Meanwhile, communities were setting up portable community shower facilities to deal with water rationing and many of the state's native salmon runs were - and still are - teetering on the brink of extinction.
A similar scenario is playing out in Oregon's Klamath basin and climate change predictions are suggesting that we're in for less rain in the future, not more. In response, Oregon State University has spearheaded a project with 30+ farmers around the state to conduct on-farm trials growing a few specific crops without irrigation. We're one of those farms this year.
On Memorial Day, OSU professor and researcher Alex Stone arrived at the farm in her pickup, loaded with soil moisture probes, ten winter squash plants and five tomato plants. She took a six foot deep soil profile sample of our field, installed 4 soil moisture probes at 1', 2', 3' and 4' depths, planted out the winter squash and tomatoes on five foot spacing, and handed me a soil moisture reader to collect data with each week.
We got the plants established with drip tape for the first few weeks, but by the end of June had removed all irrigation from the plot. Every week I record the soil temperature, the soil moisture at each depth, and the percentage of squash plants with female flowers and send the data off to the OSU team.
The vigor of the dry-farmed plants has been astonishing. They are side by side with our drip-irrigated squash plants and the dry-farmed plants are actually larger than their irrigated counterparts. They are on wider spacing - 5' instead of 2' - which allows them to forage more widely for water and nutrients. The ground is bone dry these days but the plants don't show any sign of mid-day wilting and the fruit load on both the tomatoes and the squash is startling.
We're keeping yield data on the tomato harvest each week, and will do the same once winter squash harvest commences in September. Those numbers, taken together from thirty different sites, will be key in determining the overall economic viability of dry-farming for farmers around the state. We're expecting the flavor of both the tomatoes and the squash to be superior to that of irrigated plants (less water concentrates flavor in the fruit), and research to date has shown that dry-farmed squash keep in storage significantly longer than irrigated squash.
I'll let you know what we learn later this fall. Hopefully the research will help contribute to evolving solutions in the face of shrinking water resources.
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