Tomato Stakes and Puffballs

"Ashes to ashes, dust to dust." …The Book of Common Prayer

No activity within the realm of human experience is more governed by tradition than gardening. From the earliest age, it was imprinted on my mind that there was a right way to plant everything; it had been handed down by generations of ancestors my grandmother had known personally and who were all somewhere up there watching to see that we did it right. So each summer we dried tomato seeds, stored them in jars in the cellar, and planted them in the spring when the moon was in the right sign. When the plants got a foot tall, they were tied to stakes with rags from old dresses or feed sacks. The stakes were made from small locust trees, and were kept and re-used for years. They were more than twice as tall as I was, and the vines would climb all the way to the top and start back down by mid-summer. And when the tomatoes got ripe, you were supposed to take the salt shaker into the garden and eat them, unwashed, right from the vine.

Times have changed. Tomatoes now are hybrids, so you can't grow them from your own seeds, and they have been bred to have shorter vines that can be harvested by machines. But I still find pleasure in seeing a neat row of wooden stakes in the garden, so I cut my own stakes from the woods behind the house and use them year after year until they rot and break, just like all those generations did before me. It would save time, space and labor to buy new stakes at Walmart each spring and throw them away in the fall, but I can't bring myself to do it; somewhere, my grandmother may be watching.

The garden of 2007 proved to be an exercise in futility. Groundhogs ate the bean plants, squash bugs killed the zucchini, Japanese beetles attacked the beets and lettuce, and the drought finished off everything else. Even the weeds grew poorly, and as the year dragged to a close the only thing left standing in the garden was the row of tomato stakes. The new year started the way January should, cold, windy and miserable; but then, while the west coast was buried under eleven feet of snow and the midwest was having tornadoes, Emmitsburg got several days of sunshine with temperatures near 70 degrees. This left me with no excuse to avoid taking in the tomato stakes.

There were only a couple dozen of them, so it shouldn't have taken long, but inevitably it started my mind wandering. As I pulled up the stakes the bark began coming loose from the older ones, revealing networks of tunnels where bark beetles had been feeding. There are many kinds of these beetles, and they play an important role in nature; when trees die in forests, the beetles speed up the decomposition process so the wood will rot and return its nutrients to the soil. The odd thing about this is that although these beetles eat wood, they can't really digest it; they have no enzyme to digest cellulose. So it passes through their gut and is deposited like sawdust in the tunnel behind them as they chew their way along. This sawdust is attacked by fungi, which do have a cellulase enzyme; and the beetles then turn around and eat their way through the tunnel a second time, consuming the fungi. Looking closely at places where the wood was wet, I could see the delicate white threads, or mycelia, that make up the body of the fungus in the worm tunnels. This is the process of symbiosis that we all learned about in elementary biology.

There are thousands of kinds of fungi. Some cause plant diseases like the blossom-end rot of tomatoes; some, like yeast, produce food and alcohol; some produce antibiotics and other medicines. But the vast majority of them live in the soil. They spend most of their lives as microscopic mycelial threads, digesting all kinds of dead plant material from grass clippings to tree trunks, and releasing chemical nutrients which keep the soil fertile. Periodically they reproduce by forming enormous quantities of microscopic spores, which are released into the air from structures like mushrooms, brackets or puffballs; thus the "ashes" of dead plants appear as clouds of dust. Their ecological importance cannot be overstated; they are the decomposers in the food chain, and without them all of the world's soils would be depleted of nutrients in a short time.

Puffballs are among the oddest of the soil fungi. I still remember the first one I ever saw; my father showed it to me when we were going to get the cows for milking one evening. It was a brown, baseball-sized lump on the ground by a dead log; he told me to kick it, and when I did it exploded into a cloud of brown smoke. I jumped on it repeatedly, and smoke kept coming out, though it clearly was not on fire. During the war when we played army games and searched for invading German soldiers in the woods, we found that puffballs made excellent hand grenades, except that you couldn't throw them very far. Luckily, the spores that comprised the "smoke" were not harmful, for we were covered with them.

One day last fall, Ruth Richards appeared at our front door holding what looked like a white basketball. It was Calvatia gigantia, the giant puffball; she found it growing in a wet area near her house. It had probably been growing in the soil for years as a mycelium, peacefully consuming dead leaves and sticks; several days of rain following the drought must have stimulated it to form its reproductive body, the puffball. It was the biggest one I ever saw, over a foot in diameter, pure white in color and with the texture of freshly-mixed bread dough. It was a bit over-ripe; when we cut it open the central area was turning to a gray-green color where spores were starting to mature. We cut some of the white part into slices a quarter of an inch thick, and fried them in butter; they had an earthy taste, not disagreeable but not as good as commercial mushrooms. If we had got it a day earlier it might have been better.

Most of it ended up in our compost heap, but it did not go to waste; by now the whole area will be seeded with its spores. A mycologist named David Arora calculated that a puffball that size would produce 7 trillion spores (he didn't actually count them… by my reckoning, if you counted one spore per second, it would take you over 220,000 years to get to 7 trillion!). They can float in the air for miles, and they can lie around for years before they begin to grow. We are surrounded by them; you have probably inhaled several while you were reading this article. On these warm January days they are already starting to germinate in my compost heap, and the mulch they produce will enrich my flower beds next summer. And some of them also probably will find their way into the new tomato stakes I will have to cut next spring, and begin to feed the next generation of bark beetles.