What weeds tell us

[kaviare]

This won't be knew to most people, but I thought perhaps a good topic for discussion and collection of knowledge?

I was doing some googling to find out if all those soursobs in my front yard will give my chooks indigestion, and I came accross the natural sequencing farming forum
http://www.naturalsequencefarming.co...wforum.php?f=1

I was particularly interested in the bit on caltrop (three cornered jacks, bindi) as that was literally the ONLY thing growing in my garden when I moved in. Six months later, the next crop has come up, but it's been mostly smothered out by mallow (as recently identified by this forum!) and clover, all self seeded. The only places the caltrop is still growing in where the soil is particularly poor, and where I haven't mulched. I've been pulling it up (have you ever stepped on a three cornered jack? Then you wouldn't find the little delicate purple flowers it's putting out now to be pretty!) but reflecting on it's niche in my garden at the same time.

Researching soursobs, I've found that 'feeding them to death' is a common control method, because they are suited to poor nutrient soils. The same is true for caltrop. That would explain my abundatn crops! In past gardens (I'm in SA, by the way) I've found that sowthistle, dandelion and milkthistle, etc grow in low nutrient soil, and their deep roots do wonders for it. My pet rabbits love them, so I've never considered them a weed anyway, and let them grow large enough to make a real impact on the soil, until you could see worm castings piling up at the base of the plants. In my current garden they are only growing on the very edges of garden beds, in the dampest parts of my garden.

Grass is invading the beds that were previously covered by ivy and other allopathic leaves, and I'm leaving them to do what they do until I have other things to plant there. After the grass has been there a few weeks, the mallow follows.

What 'weeds' have you noticed in your garden, and where? What niche do they fill? I know there are plenty of smart, observing people with far more knowledge than I!

[pebble]

bump

[geoff]

I find the caltrops will grow in rich soil as well, the difference seems to be cover. If the ground is well covered they wont grow, if the ground is bare then they'll spring up. They come up all through the manured vege garden if I pull out the other "weeds". This matches up with what I've read in "Weeds And What They Tell" by Ehrenfried Pfeiffer, which is that spiky, thorny plants such as thistles & burrs will grow to protect the bare earth, and will then be succeeded by other plants. That book is good, it provides the basis for analysis of soil based on the mix of weeds present. Though based on US weeds, we have many of them in Oz, and around the world I'd imagine. This year we should have minimal caltrop because there's a good cover of grass and more useful weeds thanks to the rain.

I've noticed that stinging nettles seem to invariably spring up where chickens have spent any length of time. We discovered the location of an old chicken yard on our place because it was the only spot that grew nettles. They also produce a beautiful humus where they grow.

[sun burn]

I have a few weeds growing in my garden but i don't know what any of them are called yet. There's a couple of things that grow big and have burry burs on them so i try to make sure i pull those out before they get a chance to cast their seeds.

I think i have some sort of clover though it may not be. It grows at grass level. Anyway i read that clover in the lawns you've an acidic soil so i threw on some lime to see what would happen there.

Mainly my plan is to gradually improve the soil and crowd out those weeds iwth other things. The weeds tend to grow best when the patch of soil is left unattended, no water as well as poor nutrients.

I'm also putting my weeds in a bin to make liquid compost now. Though i note that sprinkling that stuff all over is a time consuming task.

[eco4560]

I have noticed that the large crop of cobblers pegs (spiky weeds) that I have been ignoring, is gradually being replaced by purple top now. I wonder what will come next? The sweet potato is heading that way and might beat them yet....
I'd love to know what Singapore Daisy is telling me about my place..... I grow that really well. It does make an excellent ground cover that keeps the soil moist and fungal dominant. It also chokes the living daylights out of anything that I want to grow.

[kaviare]

I guess the thing is that we are ascribing purpose. So obviously, in an appropriate setting, a weed serves a purpose. But it also serves its own purpose of producing more and invading other areas. And for non-native things, the equation is a bit sweked, since the niche it fills in its homeland might not be so much empty here as uneccessary. Or it may be shoving out native plants that fill the same niche.

My current policy is not to pull anything that I am not immediately replacing, with the one exception of thigns that are 'dangerous' to my garden like caltrop and also the ivy that is smothering everything (final bit got hoiked off the fence last night, hooray!)

[heftzwecke]

There is a book to identify weeds. It's called "weeds of the southeast" from CSIRO. It is not really cheap and I only had it from the library. Lots of weeds are edible, however most of them are too fiddly to really be suitable for everyday salads. But you might add some dandelion or chickweed. I always plan to make a dandelion wine.

[Michaelangelica]

What facinates me about what weeds tell us it the mineral content of the soil
Apparently some can let you know if gold or silver or other minerals live under them. This would be handy bit of 'useless info.' to know about on walkabouts or even in your garden.

Too, most weeds produce lots of protective chemicals, it is what keeps them alive, therfore most of them have medicinal uses

[heftzwecke]

It tells you as well about your soil what's in there or what's deficient, but you must know.

[Grahame]

A friend of mine was working on a thesis about which plants indicated the presence of uranium in the ground. I suppose it is better than doing some invasive exploration