Why rain euphoria doesn’t last

Last Thursday we were fortunate to have a very nice rain, 1.3″ that fell steadily over night. Now it’s Monday, and I’m already considering my next irrigation. Why? This graph holds the answer.

moisture

This is a data log of our soil moisture after the rain that fell on the night of December 15/16. The light blue line represents soil moisture at 12″, the dark blue line represents moisture at 36″. The range represented by the shading and dashed lines is the preferred range; a fully saturated soil would be at the top.

What we’re seeing here is that prior to last week’s rain we were quite dry… very close to the lower acceptable limit. We were ready to irrigate had the storm failed to deliver. Thankfully it delivered in line with expectations. Where are we now?

The rain had the clearest impact at 12″ (light blue), which is as you would expect, but it was insufficient to fully saturate the soil. At 36″ (dark blue), the rain barely registered at all. Shallow soil moisture has already dropped considerably as the rainwater wicks through the soil.

Hoping the rain forecast for next Monday turns up!

(Hat tip to our technology providers at Acuity Agriculture for a great tool!)

#Water saving

The year just ended was dry. Really dry. Our crops needed water, yet there is a strong incentive to conserve. So for 2015 we really tried to pull out all the stops, and got our water use down to just 1.25 acre-feet of water per acre (AF/acre). For those of you who haven’t committed water stats to memory (most of you, I’d guess) here are a few benchmarks.

2.23 AF/acre- The amount we are allocated as part of the managed Santa Paula groundwater basin.

2 – 2.5 AF/acre – The typical standard for citrus and avocados.

1.65 AF/acre – The amount we used in 2014.

1.25 AF/acre – The amount we used in 2015.

I’m happy to say that despite our stingy water use, our production was actually up a bit in 2015 compared to 2014. Can we continue the trend? If this El Nino delivers, we should. But as I write this, we’re coming off three days of Santa Ana conditions with temperatures over 90 and humidity dropping as low as 9%. There are only 60 days or so left in the rainy season, and nothing on the horizon for 7 to 10 days at least. The clock is running against us.

What’s new for 2016?

034

We’ve added new technology from Acuity Agriculture that will allow us to be more observant. We can now see soil moisture in real-time, track soil and air temperatures, and even get a better handle on the drought’s less visible threat: soil salinity.

As happy as we are to see a healthier Sierra snowpack, this drought is not over, and it won’t be over this year. Not in Ventura County.