Have you ever thought about where your food comes from? When most people think of food and the plants that produce it, agriculture and row cropping comes to mind. Rows of uniform plants that fruit and are harvested all at the same time. Even if you grow all your own food, and have mulched garden beds full of different types of crops, each variety has been designed to germinate and produce fruit right in time. This didn’t happen from humans finding these perfectly uniform food crops in a forest somewhere. It happened through a long process of human societies finding plants they decided to work with and then selecting seeds from their favorite plants year after year. If a seed was too difficult to clean or store, was too small or bitter, it wouldn’t get planted, and those genetics were selected away from the new crop. This process is what made a native wild plant go from a genetically diverse wild adapted native plant, to a domesticated native plant. 

The southwest United States and northwest Mexico has some of the oldest, most diverse and nutritious agriculture in the world. Chile peppers, corn, beans, amaranth, sunflowers, and more make up a diverse pallet of nutritious food. 

Their wild crop relatives have adapted to the ecology of a system and their species is set on survival. Wild plants can’t afford to flower or seed all at the same time, and have a weird season frost wipe out their entire species. With cultivated crop varieties, humans have been making up for those stressors. Few farmers plant their entire seed store at one time, in case of frost or pest and you need a tidy “do-over.” Wild plants protect for this by having such amazing genetic diversity that they always have an option for survival, by carrying many useful traits keeping the genetic diversity of their species and population alive.

According to Colin Khoury of the USDA, “almost 4,600 crop wild relative and other wild useful plant taxa (species, subspecies and varieties) have been inventoried in the United States, and of those listed, over 1,000 (22%) occur in Arizona.” Holy moly! This article can’t get even close to doing that list justice, but we will reveal a short list: chiltepines, tepary beans, canyon grape, and agave. 

Chiltepines (Capsicum annuum var. glabriusculum) are the wild crop relative with the most charisma in our region. This plant is spicy, cute, and fairly pricey to purchase, since growing them in an agricultural setting is trickier than harvesting them wild in the mountains of Sonora. The sky island region of Arizona is the most northern range of these amazing plants. They are the wild crop relative and predecessor of chile peppers.

Tepary beans (Phaseolus acutefolius) are found in our mountains and is a wild relative of cultivated beans. It’s the most drought tolerant bean, and has been used in farming for thousands of years in this region. 

Canyon grape (Vitis arizonica) is found all over our region, from roadways to taking over trees in riparian areas. These wild grapes are important for adapting wine grape varieties to our region through rootstock.

Last but not least we have agave. Next month’s article will be about wild agaves and how hundreds of acres of cultivated agaves were grown as early as the Hohokam era. Agave palmeri and Agave angustifolia are wild relatives of some of the domesticated varieties discovered by Wendy Hodgson and Andrew Salywon of the Desert Botanical Gardens. 

In the words of Gary Nabhan and Colin Khoury from their pamphlet “Conservation and Use of Crop Wild Relatives in Arizona” published last month: “To produce good, affordable food while reducing the environmental impacts of production, more diversity will be needed – both in the variety of plants cultivated or foraged for the market, and in the genetic variation within domesticated crops. Crop wild relatives offer the world both of these gifts.”