Germination of anything - volunteering

Hi,
Just a curious thought: why does very little germinate. For instance, if apple trees grew from apple cores, the sides of roads would be littered with apple trees (ok, where they don't spray or cut grass, but you get the idea).

I can't imagine how much fruit or even purchased seed I have spread, but the germination and volunteering of anything seems to be lacking in proportion to the seed that actually touched the ground.

Is it a soil question, with more volunteering happening where soils are excellent and nothing volunteering where it is not? We have heavy clay.

Even "weed" seeds don't exactly take off like I would have imagined.

An example: we pounded a spot of ground with seed over 3 years. In a weird twist of events, we lost the land and it was tilled flat. Borage, comfrey, sunchokes, chard came back, but nothing else.

Thanks for any input.
William

Maybe it's because we live in the age of grass. Just a thought.
William

William James wrote:Hi,
Just a curious thought: why does very little germinate. For instance, if apple trees grew from apple cores, the sides of roads would be littered with apple trees (ok, where they don't spray or cut grass, but you get the idea).

I can't imagine how much fruit or even purchased seed I have spread, but the germination and volunteering of anything seems to be lacking in proportion to the seed that actually touched the ground.

Is it a soil question, with more volunteering happening where soils are excellent and nothing volunteering where it is not? We have heavy clay.

Even "weed" seeds don't exactly take off like I would have imagined.

An example: we pounded a spot of ground with seed over 3 years. In a weird twist of events, we lost the land and it was tilled flat. Borage, comfrey, sunchokes, chard came back, but nothing else.

Thanks for any input.
William

There's a few things going on there. One is that as you say, we live in an age of grass. Which is a consequence of many things, but grass is pretty hard to outcompete if humans keep doing things to support the grass.

Where I live it's land clearance for farming, overgrazing, and introduced animals (mostly rabbits). In order for anything to grow in that environment, it needs a special set of circumstances and those things aren't usually allowed by humans.

Those circumstances would happen normally very well. I spend time in native ecosystems and mass amounts of seeds germinate. I also spend time in non-native ecosystems and the plants that germinate there are the ones that are responding to the distruptions. Hence in your example it's the pioneering weeds that have seeds and roots already in the soil when it's cleared and disturbed, and those are the plants adapted to growing in disturbed soil. If that land was left to itself, there would be a succession of plants that come afterwards. Often you get annuals at the start that provide quick build up of plant matter that allows longer lived perennials to get established. Birds and wind bring in additional seed stock, and so on. Even in grass, trees will estabilish themselves eventually.

Google seed balls and maybe fukuoka if you want to see how to encourage germination from seed distribution.

Seeds contain high energy density compared to other organic materials. That makes them rich targets for predators: fungi, micro-organisms, invertebrate animals, birds, mammals, etc. When I grow sunroot seeds for example I consider myself fortunate to be able to harvest 1 seed in 40 of what the plant actually produces. And that's with only bird predation. Grasshoppers have sometimes eaten my entire crop of radish seeds.

Seeds are delicate. High temperatures and low temperatures can both kill them. Too much water can damage them. The wrong timing of temperature, light, and moisture can kill them. Sometimes they sit dormant in the soil for years before germinating.

Then, once they successfully germinate, the predators continue eating. Animals crush them. Sun burns them. Rains drown them. Frost kills them. Winds uproot them. Other plants out-compete them.

But, every once in a while a seed grows successfully and turns into a mature plant.

Around here, we have wild apple trees scattered widely: typically in riparian zones, or along canals. Peaches are not winter hardy enough to thrive here long term. I see wild peach trees from time to time, but they die out within about a decade. Some types of plums and apricots grow in the badlands. Asparagus grows wild along the ditchbanks and roadways.