The downside of dry

It’s been very dry most of the summer; readers of this blog know that. Although the drought has been frustrating at times, we’ll still take this year’s weather over the last few absurdly wet ones and all the issues too much rain causes. But the opposite of bad isn’t necessarily good; farming is the art of keeping your balance as the weather gives you whiplash. While some problems with drought are obvious (plants need water to grow), others are more subtle for non-farmers. Here’s a look at some of the issues we’ve faced in dealing with 3 1/2 months of overly dry conditions here.
First, the conditions we’ve actually seen. Through June, we were in normal to too-wet conditions. We recieved 1.09″ on July 3, and then the spigot was turned off. Since then, we’ve only gotten over .5″ in a day 4 times, never again over an inch. Total on-farm monthly rainfall through July, August, and September was at or below 2″. October has been the driest yet so far.
It’s important to keep in mind that drought (and rain) can be very localized, far more so than temperature. If we’re having a heat wave, likely much of Missouri is too. But rain can be drastically different over short distances, leaving individual farms and plots of land under very different conditions even in one locality.
The image below, from the National Weather Service’s extremely useful and addictive Advanced Hydrologic Prediction Service, shows total rainfall across Missouri for the last 30 days (as of 10/14/2011). Our farm is marked with a black dot near the center of the image; note that there is a rainfall difference of nearly 2″ between the northern and southern ends of just our county. The data are pretty accurate for us, at least: we recorded 1.43″ of rain on the farm from 9/13-10/14, right on the 1″-1.5″ line mapped by shades of green. It’s worth noting that the color scheme here could be misleading to some: in my world, red implies drought and green implies lush times, though the opposite is true here (check the scale at right).
Part of the story, though, is that most of that rain has come in sporadic, small doses that never have much effect. Rather than a good one-inch soaker that really filters in and helps crops, the rain since July has mostly been little drizzles that move the dust around and vanish the next day. Over the last week, we technically broke a 21-day dry spell, but only with individual totals of .11″ followed by a windy dry day, then .14″ followed by two windy dry days, such that whatever moisture entered the soil vanished very quickly and never made it to any plants’ root zones in meaningful quantities. Thus even the few inches of rain we’ve had each month this summer is misleading, because almost none of it has actually mattered.
So what?
Irrigation has become a serious issues. Vegetables take a lot of water to grow; a good rule of thumb is 1″/week. At best we’ve had half of that over the summer, and it’s really even less since most of the rainfall has been in small batches that doesn’t soak in. Thus we’ve been running our drip irrigation lines heavily trying to keep things happy. But we’ve started to take the drip lines out in places due to frost, so in places we have had to start using sprinklers, which are far less water-efficient due to wind and evaporation, but can cover larger areas more consistently. Newly seeded or transplanted fall crops, like spinach and strawberries that we intend to overwinter for spring CSA, take extra work to keep alive in these conditions.
The problem has gotten worse toward the end of the season, as we start pulling out production crops and trying to establish dense winter cover crops like oats, rye, and vetch whose job is to grow into a nice thick stand before winter and protect the soil from freezing (or blowing away; see below). Instead, these either haven’t germinated, have taken lots of sprinkler/hose watering to germinate, and/or have barely grown. The paired photos below show one of our northern fields which was planted in rye/vetch almost a month ago in antipication of forecasted rain which never meaningfully materialized. The seeds germinated and grew about an inch, but have looked the same (below right) ever since. This should be a good, lush, soil-protecting stand by now. Instead there are clouds of soil blowing around on windy days, and the plants are alive but barely growing. We have far more bare soil on the farm than we’re comfortable with, but can’t get cover crops to grow well enough in this brutal combination of drought, warm weather, and regular high-wind days that suck the moisture from everything. Even running sprinklers on this field hasn’t had much effect.
Soil hardness increases as the ground dries out. This can make it hard to turn in manure or otherwise work the soil, and has been especially frustrating for handling fences and posts. The portable net fencing we use for goats and pig has gotten harder and harder to set up and move, as the posts won’t go into the rock-hard soil. We had a mass goat escape recently as a fence post just fell over, opening a gap, and a similar thing happened to the pig fence.  As we clean out beds of peppers (below left), tomatoes, cucumbers, and other items that were trellised using T-posts and string, we find that the posts just won’t come out of the hard ground. We’ve been digging them out with shovels one by one: the one shown below right wouldn’t come even with that pit dug around it. Also notice how dry the ground is; most of the pepper plants are healthy, like the one next to Joanna in the photo, but there isn’t much moisture to spare down there and it’s taken a lot of irrigation even so.
Rodents have become more and more frustrating this year. We always have some damage from voles, it’s part of the trade-off for permanent no-till vegetable beds, but they’ve been especially aggressive in tunnelling and damaging things this year. We think it’s largely due to the drought; the only water available on the farm comes from our irrigation lines, and the voles naturally tunnel along right underneath, messing up the root zones, collapsing plants, and eating root crops like peanuts which they find there. They can also start gnawing on the irrigation lines themselves, looking for water. Many of our young blueberry plants have been mostly undermined and thus near-killed by rodents; you can practically reach into the caverns excavated within their root masses, where the water is. Snakes are the best defense against rodents, but we’ve seen very few snakes this year for unknown reasons.
Pastures, of course, suffer too. We keep our goats on pasture 24/7 from late spring through fall, rotating them regularly to new ground. Usually this allows the pastures to recover and regrow after grazing, but this year they’ve stayed brown and dead post-grazing. We know we’re managing our pastures well overall because our milk yields this year have been equal to or higher than last year, even with drought-stressed pastures, but we’re now running out of places to graze and the yields have really started to drop. In a wet year we can start over on pastures grazed early in spring, but those haven’t regrown much this year. One farmer at market told me that they normally don’t start feeding out hay to cattle until December, but this year they’ve already started. We’re trying to supplement with bean plants and other farm-generated material, but are having to use more purchased hay than desired as well.
Wind/erosion was mentioned above, but needs more explanation. As soil dries out, it becomes more prone to windblown erosion. We’ve had a lot of windy days this summer, even with our protected valley, and many days you can see soil blowing away. Often this is the really good stuff, and it’s a real loss. We take soil conservation very seriously, it’s one of the benefits of our permanent no-till vegetable beds with sod aisles, but we can do relatively little against windy drought. Mulch can help, but this dry year has struck in the middle of an intentional transition away from purchased straw mulch (expensive, seedy, otherwise problematic) to on-farm mulch sources like aged leaves, meaning we don’t have as much on hand as past years. Increased cover-cropping is another way to hold soil in place, but as discussed above, it’s been much harder to get these to germinate and grow under such dry, windy conditions. We’re losing far less soil than your average bare giant commodity field, but we still care about it. Plus, high winds and low humidities are just personally uncomfortable: we have to drink a lot more water even on cool days and be otherwise careful of conditions.
Pig rooting becomes less effective. One of the side benefits of pasturing a pig is its ability to naturally root up unwanted grass like fescue so we can reseed and improve the pasture: it’s an edible tiller that fertilizes as it goes. However, this year, the ground has been so hard and dry that wherever we put him, the pig hasn’t been able to do much with it. We’ve run a hose and sprinkler out to him, which creates a small wet zone that he indeed has turned up nicely. But that’s not practical at a larger scale, and so we’ve lost most of the year’s potential pasture-improvement benefit. Instead he’s mostly just hard-packed anywhere we’ve pastured him, making things worse instead of better. This one we didn’t see coming.
Still better than monsoon, though. We’d like a nice balanced year sometime, but will keep plugging along with what we get. We’ve seen some form of the two extremes these past two years, from way too wet to way too dry, so are getting a handle on managing both. Overall, dry is better. But is a nice, soaking 1″ of rain too much to ask even once a month?

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