Climate Adaptive Demonstrations
From 2023-2025, we will demonstrate Climate Adaptive Strategies at the NWREC Learning Farm
These experiential demonstrations will focus on drought-resilient and climate-adaptive production strategies and will include techniques such as dry farming, low and no-tillage, tarping, and drip irrigation systems.
These techniques have been identified as crucial needs by our farmer networks in light of Western drought and wildfire conditions.
Workshops and Field Days for Climate Adaptive Strategies for Small Farms NWREC Learning Farm Project
2024 SUMMER FIELD DAY
Blog Posts
July 19th 2024
Updates on the dry farmed and deficit irrigation demonstration trials:
The field day will be Thursday, August 28 from 5:00 to 7:00 pm at NWREC in Aurora.
This year at the Learning Farm, we’re growing melons! The melons were transplanted on June 7, 2024, and thankfully, there was some rain not long after planting. We’re combining what we learned last year from the dry farming and irrigation scheduling plots and putting it all into one demonstration area. This year, we have dry farmed melons, two deficit irrigation demos; and one demo where we are irrigating about an inch of water per week. We are growing five melon varieties, and all of these are in each of the demonstration plots. Once the fruit is ready to harvest, we’ll be looking at maturity dates, yield, fruit quality, and sugar levels.
Installing a soil moisture sensor near melon plants.
The moisture sensors are installed within the plant rows, and the drip irrigation is about 6 inches from the plants. We’ve been noticing that the water is not reaching the moisture sensors in the deficit irrigation plots. Our first irrigation was on July 10 in the 30% depletion plot, and we didn’t see as much of an increase in soil moisture as we expected after one inch of water was applied to these plots. We’re looking more into this and are taking notes for next time, perhaps putting two drip lines down on either side of the plant for more even distribution.
Piper Westhead with melon field in background.
Melon field one week after transplanting.
We’ve been working with Lucas Nebert and the OSU’s dry farming project to determine deficit irrigation rates; we are using 30% and 50% of available soil water depletion. When these levels are reached, we irrigate these plots. Soil moisture sensors were installed at 6”, 12”, 24”, and 36” depth in Lilly, one of the melon varieties, in each of the irrigation demonstration plots. These sensors were installed ten days after planting. The readings from the moisture sensors inform when to irrigate the deficit irrigation plots.
Soil Moisture Sensor readings at 6”, 12”, 24”, 36” in each treatment. Blue drops denote irrigation applications (in inches), and clouds represent precipitation events (measured in inches).
Piper Westhead, an OSU horticulture undergraduate student working on this project, has been taking soil moisture readings this season and created the graphs above to illustrate water use and irrigation of the demonstration plots. In these graphs, as the numbers go up, it denotes a decrease in soil moisture.
Largest Lilly melon in the field is in the 30% deficit irrigation plot. The melons are increasing in size and we hope you’re able to join us for the field day: August 28th from 5:00-7:00 pm.
August 7th 2023
Updates on the reduced tillage sweet corn demonstrations:
Assessing Soil Hardness
We used penetrometers to replicate the force needed for a root to move down through the soil. On August 3, we measured surface (6”) and subsurface (18”) hardness in the sweet corn by slowly pushing the penetrometer through the soil of each treatment. The sweet corn was being irrigated at the time of sampling. We recorded three readings of each bed for six total samples per treatment. The penetrometer scale runs from 0 to 300+ psi, readings exceeding 300 psi indicate root growth inhibition and the presence of hard pans.
Figure 2 Compost spreader may have increased compaction in the trial beds.
Weed levels
We observed distinct differences in weed levels among the tillage treatments. To accurately quantify these differences, we recorded the time it took to weed each treatment. Victoria and Heidi conducted the hand-weeding for each treatment collaboratively. The sweet corn is planted in 40-foot beds, with two rows per bed and two beds per treatment.
There were hardly any weeds in the no-till plots, while the conventionally tilled plots had a robust population of grass. It took just over twice as long to weed the conventionally tilled plots compared to the reduced tillage plots and eight times longer than the no-till plots.
Penetrometer Readings of Sweet Corn Tillage Demonstration (psi)
Surface level compaction had the greatest resistance in the no-till plots and the least resistance in the reduced till plots. Subsurface compaction levels were similar across all three treatments, ranging from high to very high. The presence of hardpans varied from depths of 3” to 15” to none throughout the treatments. We were unable to break through the shallow (3-6”) hardpan in one of the no-till beds. These beds were tarped this spring, and a farmer we interviewed mentioned that rain hitting the tarps could increase soil compaction. This may explain what we are observing. Additionally, we encountered compaction from the wheels of the compost spreader, which did not align with the wheel tracks of our beds.
Figure 3 End of beds showing weed pressure of tillage treatments
Total Weeding Time & Amount of Weeds in Each Treatment
May 22nd 2023
We applied 3 inches of compost to the tops of each bed. The compost was worked in differently depending on the demonstration.
Dry Farm plots with a perfecta.
Conventional Tillage and Irrigation with a rototiller.
Reduced Tillage with a harrow.
No-Till we raked it smooth and left it directly on top of the bed
Lucas Nebert and Clint Taylor look at sub soil sample
March 28th 2023
Last week Lucas Nebert (OSU Dryfarmed Corn Project) came out to NWREC and used his bucket auger to collect sub soil and determine site suitability for the dry farming demonstration.
The soil was well drained all the way down and was free from significant compaction layers. No grey (anoxic) layers were observed in this sample.
Lucas collected soil from the 24-36 in layer for nutrient and pH analysis.
We plan on replicating some of Lucas's squash trials this year and will be growing Delicata (Zeppelin) and Georgia Candy Roaster.
March 21st 2023
After a hard rain, puddles formed on the tarp. It seems the cover crop is too tall and it is pushing the tarp up in places.
We had a dry window for a few days so we flail mowed the no-till plot and the agrivoltaic plots. We replaced the tarp in the no-till and plan to roll out the tarp in the agrivoltaics soon.
Tarp about to be re-installed
Tarping the NWREC Learning farm
Tarp installed over no-till demonstration
March 7th 2023
As part of bed prep this spring we tarped a 20x60 ft section of the Learning Farm. This section will be our No-Till area for the next three years.
The field currently has a cereal rye & vetch cover crop. Tarping with black plastic deprives the plants of light and will eventually smother and kill the plants underneath. It also has the added benefit of warming to soil and keeping late spring rains from saturating the soil, allowing us to get into the field earlier than usual.
The tarp is 6 mil black plastic