Does your zucchini have an ulterior motive?

The final fruits of summer are ripening. It is time to pick apples, find a lingering blackberry, and maybe discover a hazelnut that the birds somehow missed. If you lived here a thousand years ago, you might be drying the fruits you find and putting them in birch bark baskets to protect them from bacteria and insects. (Birchbark contains phytochemical compounds which act synergistically to achieve antimicrobial and insect-repelling effects.) Wild animals are foraging the newly ripened seeds and final fruits of the summer, too.

Some of us plan our weekends around fall cider-pressing events, or find ourselves hurriedly make zucchini bread to use up an overflow of garden produce. We congratulate ourselves on the bounty we’ve grown, foraged, and prepared or put by for later.

However, it may be more accurate to consider that instead of us making use of the plants, they are making use of us! In fact, plants have “trained” animals all over the world to ensure their reproductive success by dispersing their seeds for them.

To do this, plants ensure that their seeds are packaged with tempting sugars, protein, or fats that attract birds and other wildlife. Our garden plants have evolved to produce fleshier and sweeter fruits to encourage us to plant more of them. The seeds of some plants, like winterberry (Ilex verticillata), will not germinate until they have passed through animal intestines. The seeds of others, such as trillium, have oily appendages called elaiosomes containing rich lipids and protein which are highly attractive to ants. The ants carry the seeds home to their colonies, where they feed the elaiosomes to their larvae and then “plant” the remaining seeds in their compost piles, providing a fertile start for a new plant. Plants are master engineers and more.

Here in a colder climate, many animals depend on this nourishment to survive the oncoming winter, whether their strategy is hibernation, migration, or other adaptation. Every little rodent flirts with danger every time it goes in search of a seed, lest it be caught by a fox or owl, but it has little choice. Every seed-eating mouse and vole must find food, regardless of the risk. Plants control where these rodents go, how often, and what happens next. From this perspective, it’s plants that orchestrate animals’ movements within their various habitats.

So go ahead, enjoy your apple-picking this fall – but don’t take all the credit for a bountiful harvest. The plants planned it!

Photo: Jack-in-the-pulpit seed stalk