Over on WUWT, I left a rather long comment on one thread. I’m reproducing it here so I can have the links available in the future. This first quote is from the article at the top of that posting.
I would also add this link:
It has an extensive list of the various plants we can eat in “hard times” if we really need to do so. From the leaves of those green beans that we presently disc under or consign to the compost heap, but eaten in Africa as a ‘pot herb’, to Kudzu that’s all over The South (and forbidden to be brought into California since it grows so well) and more. Heck, even rose hips are edible, as are a few dozen “ornamental” plants we grow just for looks. But for now, back to the original quote from that WUWT article:
“Moreover, a 2-degree drop in average global temperatures would shrink growing seasons, cropland and wildlife habitats.”
A modest quibble. It is more “move” seasons and habitats than “shrink”. Much of it can be adapted to via swapping crops. This is a large and complex topic (basically most of what farmers do) so only a couple of short examples.
1) Phoenix Arizona. The “down season” for gardens there is mid summer. It’s hard to grow things in July, August, and sometimes September. So what to do? They grow heat adapted varieties, or plant heat sensitive things in winter, spring, and fall. Now, as things cool, summer “hard time” becomes “good time”. I’ve pointed this out going the other way: That growing crops is not heat limited until a place is as warm as Phoenix Arizona. I.e. about 120 F+ or about 50 C+. In this case of cooling, Phoenix in summer becomes available for growing crops other than those particularly suited to a hot desert.
2) Iowa. At present, it grows a LOT of “field corn”. Field corn is not eaten by people (other than a few hardy souls …) and is a tough hard grain mostly fed to chickens, pigs, etc. It can easily take 100 to 120 days to mature and it really likes the heat. If the summers get cooler, there are cooler crops that can be grown. Go more north, you get more wheat. Above that, rye. Eventually you run into barley and buckwheat. BTW, you can also grow barley in Arizona… just adjust your season. Think on that for a minute. Barley is grown in Alaska, and Arizona… Think you can get it to grow in a 2 C different average?…
Barley is very adaptable to various environments. In fact, it is the most adaptable of the cereals. Barley is an annual grass that has two growing seasons, winter and spring. It does best in the spring in a temperate zone with a 90 day growing season, it can also be found growing in sub-arctic regions, like in Alaska or in Norway, with very short growing seasons . Barley also has a very good resistance to dry heat compared to other small grains. This feature allows it to grow near desert areas such as North Africa.
You don’t need 90 days. There are some very short season barleys. Historically, it was far more common than corn, but over the last century, corn has taken dominance. Why?
U.S. producers harvested 2.24 million acres of barley in 2011 with an average yield of 69.6 bushels/acre. Total production was 155.8 million bushels, which was the smallest annual production level since 1936 and approximately one-half of the 2000 production level. Much of this decline can be attributed to increases in corn production in northern climates that have historically produced barley. The advent of shorter-season corn varieties, coupled with record corn prices, has caused production substitutions away from barley towards corn.
Because of “short season” varieties of corn. Unlike the original Indian Corn that was typically a 75 to 100 day corn even for eating as roasting ears, I have in my seed archive a 45 day sweet corn. Yes, it’s a bit of sellers puff in that where I am it takes more like 50 to 55 days in reality, but still, it’s a whole lot faster than it was.
Grow and plant barley as you would wheat. Some varieties are spring planted and some are fall planted. Barley ripens sooner than wheat; spring-planted barley ripens in 60 to 70 days, fall-planted barley about 60 days after spring growth begins.
So as “growing season” shortens from 120 days ( or in some places even up to 270 days ) we can substitute other shorter season crops. Such as Barley. (This glosses over an important point: In many cases we have gone to ‘double cropping’ as the season length of the main crop has shortened… so barley is now often grow in addition to corn. So for this double cropping to continue, we would need shorter crop cycles, as we have developed for many crops over the years…)
We don’t grow barley all the time because we want corn more, for a variety of reasons from having the corn drilling and harvesting equipment to being familiar with it to liking the sound of “corn fed beef”… but barley is fine for cattle feed too and we can eat it (or drink it ;-) if needed.
So is that IT? Just barley? Well, no. Ever hear of “buckwheat cakes”? Yeah, we don’t eat them as much now, as we have SO much excess wheat it is silly. But Soba noodles in Asian cooking and buckwheat pancakes are still pretty good.
Why Grow Buckwheat?
Buckwheat is a short-season cash crop with properties that can make it fit specific situations on your farm. While it is unlikely to be your main crop, it can be a worthwhile part of your overall farm plan.
Reasons to grow buckwheat
Fits into rotations at a time when fields might otherwise be idle.
Can be grown as a catch crop where another crop failed.
The check arrives within 90 days of sowing.
Inexpensive to grow because it requires no pesticides and little fertilizer.
Can be grown with equipment available on most farms.
Requires little attention during the growing season.
Mellows the soil and suppresses most weeds.
Easily raised organically, at a premium price.
Notice, in particular, that line about the check? From seed in the ground to delivered to the customer for payment in under 90 days. It really likes about 70 F as ideal. So until Iowa has summer temperatures under 70 F and a growing season less than 2 1/2 to 3 months, we can grow grains there.
And don’t even get me started on kale… Siberian Kale has been harvested from under light snow… Historically, Amish farmers (my ancestors, BTW) grew various beets and turnips for cows. Why? They grow in the cold reasonably well, and keep very well in very cold conditions. Sadly, many kinds of “fodder beets” are being lost as varieties since we now just grow warm season feeds like corn, soy, and alfalfa hay… but some folks have kept a few of the varieties around.
Fodder beets have been around since the 1400s if not earlier. These beets were prized as nutritious animal feed that was easy to store. Fodder beets are hardy, adaptable and palatable. They are ideal for planting in late summer for use as a winter and spring crop.
Red Mammoth Mangel Beets produce an incredible mass of edible beet leaves and a large root up to 20# or more in size! These beets prefer deeply tilled, free draining, sandy soil to achieve full size. Simply allow your animals to graze on the tops, cut the tops for feeding or harvest the root.
Surprising how juicy and sweet these giant beets are!
1940 Oscar H. Will Pure Seed Book says…
“The heaviest yielder and most popular of all Mangels the light red roots are pinkish fleshed and grow well out of the ground. Yields run as high as fifty tons to the acre.”
This is a sure way to put away enough food for your animals as they face the cold winter. Leave them in the ground and harvest as needed. Unless you are covered with snow, then I suggest you root cellar them.
So there are many “old ways” of getting through a very long winter with a short season for growing things that are only expecting mild warmth. You can harvest these things at about 60 days, but 90 days gives a better yield for cows (a bit fibrous for people then).
It’s a long list of such things…
But the basic idea is really pretty simple: We grow what we grow now not because it is the best product, or the fastest, or produces the most, or is the most cold tolerant. Mostly we do this because it is what we want. If things got tough, we could rapidly want something else that was faster… or more cold tolerant. Instead of “corn puffs” for breakfast, we could go back to buckwheat cakes… Until Iowa is under 70 F in August…
So, IMHO, there isn’t nearly as much disaster looming on the crop front as this paints. Yes, it would be a big problem to lose the northern bands of Canada and Siberia. Yet we would be gaining growing time in Arizona and Mexico.
There is a real problem with the change, but it isn’t the loss of crops to cold. It is the loss of crops to rain and wind.
During the LIA, much tall wheat was lost to “blow down” or “lodging” as the gusty strong winds blew it over. Newer short stem varieties can help with that, but not stop it. Similarly, it does no good to say “we have a shortened growing season from 180 days to 90 days, so go plant barley” if the fields are full of mud. Excess rains were a big problem for crop production in the LIA. So look more at the winds and rains (and mud). That’s where there will be a problem.
For simple cold, crops will all just move southward a couple of hundred miles in terms of who grows what where (with some far north corn moving to south Texas where they grow sorghum and millet in the heat…) and for shorter growing season, varieties will shift to short season types that match the available time. In severe cases, folks will swap to the traditional “catch crops” like buckwheat.
And none of this is even getting close to “exotic” methods. California provides most of the table vegetables for the USA (and fruits and nuts for the USA and for export). Anyone could replace California in that role at slightly higher prices using greenhouses. California uses a lot of them already. (You get about a 5 x to 10 x increase in yield per acre, but with higher costs. For things like lettuce, the increased quality means folks will pay up for it – so many specialty lettuces are now hydroponic greenhouse grown. Look for butter lettuce in plastic containers with a clear root lump still attached as an example.) Greenhouse tomatoes are taking over the world, and in Saudi Arabia they grow a lot of “truck vegetables” in greenhouses using desalinized water. All you really need is sand and ocean to grow loads of vegetables at reasonable rates – just not quite as cheaply as in Mexico or California dirt in most years. See: http://seawatergreenhouse.com/ for example). So in a real “aw shit” you would find Arizona and The Outback of Australia and The Sahara and… all putting in pipelines to the ocean and building greenhouses. Yes, costly. Your dinner salad might cost you a $1 more… depending on how far you are from an ocean and desert….
Who suffers from that? The cows and chickens and pigs who wanted Cow Chow and Pig Chow made from heat loving corn and soybeans (which we grew in the first place because Iowa in August is more like 105 F than 70 F) and instead have to eat barley and buckwheat, or the ‘slash’ from our greenhouse vegetables instead. Then again, pigs and chickens like that rather a lot and cows are quite fond of beet tops…
We are up to our eyeballs in food in the USA and it just isn’t going to make a bit of difference to us. (Folks with dysfunctional governments, like just about every country in Africa and the Middle East other than Israel will have a very hard time of it as they get drought when things get cold and do not have the stability to do much more than basic ag and certainly will not be making greenhouses fast enough… they depend on the USA for wheat, corn and soy to far too high a degree, so they will suffer.)
(BTW, it isn’t just grains… beans too. Tepary beans grow in the desert heat, peas and favas in cold and wet. Just changing which to grow is enough for everywhere but the very edge, and what is lost at the very cold edge tends to be added at the too hot edge…)
Yes, a long rant. But Dad grew up on a farm, and I grew up in farm country, and I really do wish folks would talk to farmers before saying that a couple of degree change is going to end farming and food supply… Cattle can graze from scrub desert to frozen Canadian north, too, so it isn’t just grains and beans…