Apple Trees in a Wild System
Feb/13/2014 10:49 AM
There is a lot to be learned from thinking about the apple trees' role in a wild system. One place to look is the forests in Kazakhstan where apples evolved. The apple trees in the Kazakh forests are canopy trees that share the forest with lots of other plants and other creatures, and undoubtedly benefit from many partnerships there. Perhaps the most important are the soil fungi, which form partnerships with plants that give the trees greater access to water and nutrients. The soil fungi, in turn, are nourished by their connection with their plant partners, and by the organic matter that hits the forest floor which they can break down to feed themselves. Pollinators are an essential partner as well, of course, and any natural system has flowers to feed pollinators all the time. In addition, in any natural system the diseases and pests that challenge a plant force it to defend itself by producing phytochemicals that function as micronutrients and antioxidants for those of us who eat the plants. So the tissues of a wild plant will be richer in those nutrients than a conventionally grown plant. There are good studies (see the Rodale Institute) showing that organically grown plants exhibit a greater abundance and diversity in the chemicals plants use to protect themselves, like their counterparts in a wild system.
The wild Kazakh apples are incredibly diverse in terms of shape, size, and flavor components, especially when compared with the apples we grow commercially. However, because of the way apples are propagated, there is still a huge amount of genetic diversity even in our seemingly over bred modern cultivars. I can look around our own orchard at the wild seedlings that have come up (which are likely offspring of cultivated varieties) and see a great deal of variation in size, color, and content of tannins, acids, and sugars. Because apple varieties are grafted, one variety is like one individual in breeding of any sexually produced creature, like a dog or a plant grown from seed. For instance, the first MacIntosh apple began growing, perhaps, around 200 years ago; all MacIntosh trees grown since that time are from a genetic perspective all the same tree. So, if you trace the lineage of any cultivated variety, it is relatively few steps back to a wild ancestor. This means that there is still a huge amount of diversity in apple genetics relative to other cultivated creatures (crops or domestic animals). So a lot of wild traits crop up in a single generation, when breeding two cultivated varieties. In a natural system this diversity allows individuals to do well in lots of different environments or in an environment that changes a lot, including temperature, length of season, different disease and pest pressure, etc.
We can apply some of what we learn from observing natural systems to our managed orchards. If we can set up fungal soil ecosystems with plenty of sun in our orchards, we provide a lot of what the ancestral trees experience, and hopefully encourage fruit that reaches the potential of what the variety can provide. We do this by feeding the fungi with woody biomass and/or fungal compost. For pollinators, we must make sure they have flowers available throughout the season and not just during apple blossom time. As organic growers, we find that organic or untended apple trees tend to have more diversity in flavor than conventionally grown apples of the same variety, perhaps due to the challenges our trees face from insect and disease pressure. This leads to great nutrition, and more intense flavors in the apples. Finally, we plant a diversity of tree varieties to benefit from the strengths each variety has. Sometimes we find a variety that consistently does not do well in our conditions, but more often we end up with a diversity in flavor, preferred growing conditions, and resistance to pests and diseases that means each year some varieties are at their peak while others take a rest.