Corn Pollination

This is the time of year to really buckle-down into seed saving, which is a simple prospect for many of our garden plants. Lettuce, for example, you simply let go to form a stalk and a bunch of little flowers, which then form seeds with fuzz on them like dandelions. With tomatoes you take the mature fruit, gut it into a jar, and let it sit a few days to ferment the protective layer that coats each seed. Both of these vegetables have something glorious going for them from the gardener's perspective: they are self-pollinating. Each flower has both necessary parts, fertilizes itself, and keeps unwanted crossing to a minimum.
Not so, of course, with corn. I won't go into any depth on the biology of corn pollination, since I wrote about that in an earlier post. But I would love to share how I deal with the question that follows that understanding: How does a person get pure seed under those conditions? Especially if they live in Corn Country? Especially when, if their seed gets contaminated by genetically modified crops Monsanto comes and sues them like they've been doing to lots of small farmers.
My solution comes from Seed to Seed, by Suzanne Ashworth. It is one of the great, comprehensive seed saving books for anyone who wants to understand the ins and outs of the subject.
Because it is a time, energy, and focus-intensive process at first, I started last year saving from three Hopi Blue flour corn plants. This year we planted out the resulting successfully-saved seed, together with some of the same variety bought from a catalog. The reason for this is that, in the case of most plants, genetic diversity is important. Seed to Seed recommends, as an absolute minimum, that 100 corn plants should be saved from. You will end up with 50 ears, though, because half of those plants will be participating only by tassel.
Maybe I should explain the method now...
There are two vital elements in corn pollination: the tassel (which releases pollen), and silks (which accept pollen). One silk only accepts one pollen granule, which will become one kernel on an ear. So essentially we need to stand between the silks and ANY tassels.
The best way to do this is by bagging ears before the silks emerge. Choose the best ears right before the silks come out (the only tricky part) and clip the tip of the husk off to see the bundle of silks. They grow fast, like an inch a day, so by clipping them like this they will all be the same size in one or two days when you remove the bag to pollinate them.
The next step comes one or two days later: the collection and distribution of pollen. Get more bags, stick them over tassels and staple them close to the plant, so no pollen drops out. Do this early in the morning before they start shedding pollen. Before it gets hot that day (hot enough to destroy the pollen in the closed bag), say maybe 11am, you take the bag off, bending and shaking the tassel as you do, and then you have a little pollen. Collecting and mixing all the pollen in one bag, you have quite a bit of it.
At that point you make the rounds of your bagged ears. Take off the bag, pour some pollen on the now-emerged silks, and then put the bag back on to mark the ears you selected.
It is a simple as that. As mentioned above, the only tricky part is trying to identify which ears have almost emergent silks. I cut the tips off of many husks only to be disappointed. But, as with many other things, if you don't start and fail a lot, you'll never know what you are doing!
So to sum up the ideal situation: 1) snip tips and bag 50 ears, 2) one or two days later bag 50 tassels from plants whose ears you did not bag, 3) collect the pollen later that morning and pollinate the 50 aforementioned ears. Done! Sit back and watch them grow, and harvest them when they are mature and dry.
Corn and squash are really two of the most difficult plants to keep pure seed from, so if you are feeling adventurous some year, do your reading and jump into it! Once you have it down, you can probably make at least a little money selling the results to a seed company.

Corn Nuts

We, like industrial America, value corn highly. The difference is that we are not going to make high-fructose syrup, ethanol, or plastic out of it. We are going to eat it! And, of course, feed the stalks to our compost.

We grow three categories of corn here, for three different purposes: flour corn, sweet corn, and popcorn.

The flour corn doubles as a high-calorie multi-purpose food and high-biomass compost crop. According to How to Grow More Vegetables an intermediate yield for flour corn is 17 lb/100 sq ft for seed and 50 lb/100 sq ft for air-dry biomass. Which is a whole lot of seed and stalk. Last year we came close to the intermediate seed yield and exceeded the biomass yield in two beds.

And different varieties will perform at different levels.

But high yield isn't everything - we aim for aesthetics, too. The photo above shows, in order, Bloody Butcher, Hickory King, Seneca Red Stalker, and Hopi Blue. Talk about fun colors of cornbread! On the right is some Oaxaca Green from the Ecology Action site.

At the Golden Rule Garden, since we are producing food for a community (as well as learning, teaching, and researching) sweet corn also plays an important role. Who doesn't like sweet corn? This year we are growing two open-pollinated varieties! Those of you familiar with sweet corn or seed catalogs know the prevalence of hybridized sweet corn varieties, so I might as well take a moment to talk about them.
Many plants (corn, for instance) spread and accept pollen freely. This is a wonderful way for them to find new genes and increase their diversity, because the pollen doesn't always land on the same variety from which it originated. If this foreign variety accepts the pollen, then it is cross-pollinated. The seed resulting from this cross-pollination, a hybrid, will grow a very nice plant, mixing characteristics of the two parents. And, most often, this new hybrid plant will produce either sterile seed or seed that grows into plants with unpredictable characteristics. Not so helpful if you want to save seed from year to year.
Seed companies began selling hybrid corn in the first half of the 20th century, and it has sold well to this day for two reasons: first, because of a condition called "hybrid vigor" that predictably occurs when two inbred varieties cross. The first generation of this hybridization is taller, bigger, and higher-yielding than either of the parents. Following generations of this hybrid plant will be much smaller and, as mentioned above, have unpredictable characteristics. The second reason it sells well is that it is almost the only thing sold. Go ahead and search your seed catalogs for non-hybrid sweet corn. Burpee's website offers 34 varieties, 2 of them open-pollinated, the rest hybrid. Because corn crosses so easily, there are few farmers or gardeners who go to the trouble to save their own seed. So if they are going to buy seed anyway, why not buy seed for vigorous, high-yielding plants? An added bonus for seed companies is that the details of what varieties they are crossing are proprietary information, so even if you wanted to go to the trouble to hybridize plants you would have to do your own years of research.
Ok, so that's the deal on hybrids. Look forward in the next month to a post about hand-pollination of corn, which is the best way for a small garden in the midst of corn country to save their own pure seed.
Finally, we are growing one variety of popcorn: Vermont Red Kernel. Margo and I are regular popcorn eaters, so we want to invest in that knowledge now. The downside of both popcorn and sweet corn, in Grow Biointensive terms, is that they create much less biomass. Flour corn might produce 48 pounds of air-dry stalks per 100 sq. ft. for compost material, while a good sturdy sweet corn may only yield 24. Probably less. And popcorn will probably be less yet. I'll let you know when we get the yields this year.
On the right is Jerry, a past intern, with his [open-pollinated] flour corn, 14 feet tall.