Learning by example is great. Such as about how to harvest a wild plant by taking “no more than”, if one knows that area and plants and harvesting outcomes to maintain or increase the number of plants, or, vastly less, if not, taking care. Half is sometimes given as a rule of thumb. If a gardener, half might seem little. If a forager, half might seem much too much, until a need is great, then again too little. The council to harvest half, might become have halve of half – as the somewhat rhetorical question, “what happens if when harvesting a wild plant, no more than half should be taken, but that happens many more times than once?” might be answered by an outcome of over-harvesting, depending on the previous years’ harvests, plant health, regeneration rate, soil compaction or aeration, soil amendments, etc., and so might be answered by have half, or halve the half, or have half of the half of the half, or wait for another year for that location.(Thats a long sentence. I rather like the sentence, though not well written, needing re-writing.)
On the topic of planting native plants, and how to harvest them, an excellent collections of writings is edited by Rosemary Gladstar and Pamela Hirsch “Planting the Future”- p. 126, discusses harvesting a plant, and they note that the plant “gains new ground each year, nurtured by reverence and the rich forest compost of undisturbed ground.” ( Michael and Nancy Phelps, p. 126, edited by Gladstar and Hirsch), though the plant is harvested by people together. The subject also is discussed in Rosalee de la Fo^ret’s and Emily Han’s book “Wild Remedies”, and much excellent information is in Maria Groves books, and also shared online on the Wintergreen Botanical site by Maria Groves – go to her 2016 Harvesting 101 guideline – its great, and very pleasant to read).
Animals harvest also . Luckily, animals are gardeners also, planting seeds, and pruning, as well as harvesting, often harvesting mindfully. Sometimes it seems not – but then, maybe with what they return to the soil, the plants return. Sometimes though, depending on flora and faunal populations, animals too might overharvest. Of course, they might also “over” harvest some caterpillars, for example, helping plants out.
No-one would purchase and plant a native plant if they knew , for example, the plant to be enjoyed by their front stoop, while they themselves still enjoyed the plant and held it in high regard, or even someone in the future lived there and cared for it, might be harvested almost fully one day by a human or humans without regard to such (even if harvested with good intention, by half, and then by someone else by half again, and so on – some harvesting might help a planting that has become many, and some, might not – if one notices that a plant could use thinning, ask). Unless, of course, it was planted with the intention of consumption, and also such unplanned sharing, which is a good idea if a person is able to plant seedlings making that idea affordable, or otherwise make it affordable, and make obvious what plants have been selected for such a project. Seed and plant swaps are probably a better idea, but on streets where gardens meet sidewalks, and sidewalks are next to home plantars, its an idea perhaps.
Otherwise, its likely plants are planted for the enjoyment of seeing them grow as well, for their shape, color, and form, and an unmindful collecting of plants does not contribute to community well-being.
Probably a caretaker or owner-caretaker of a property would not either buy plants if they knew that an animal or many, might immediately fully harvest it.
After such over-gathering, it seems it might take years for a plant to regain the confidence to attempt to re-grow in that location. (I sort of think that sentence is not overly anthropomorphic. It might be though, and perhaps others might know differently).
Unpleasantly devious thought #1. If an individual or group of people wanted non-native plants in a landscape, they might overharvest native plants from a landscape so that designers are notified by frustrated owners, and to counter plant harvesting on private or public lands, they would plant non-natives – possibly just those the over-collector hopes to have access to. Thats a bit too devious and convoluted though, isn’t it. Probably over-harvesting happens because it just does, though, shouldn’t.
Unpleasant thought #2: If a company wanted any plant out of the wild, or off the market, they might likewise be manipulative in order to achieve this. But hopefully not. Hopefully the primary purpose of chemical industries making chemicals for health, is for health, and to take pressure off of the over-harvesting of plants.
People buy and plant and harvest native plants because they are excellent in the landscape for living creatures and life. There is a balance that is maintained between non-native plantings/plants and native plantings/plants. Maybe this has always been, everywhere. Ocean barriers, notwithstanding. Whatever “ocean barriers, notwithstanding” means (I wrote this, just don’t want to talk about it in this paper, but there are icebergs, and boats, and floating trees, and birds moving continent to continent…).
Perennial plants once planted, or sown and germinated and grow, need time to develop, and to develop colonies. Years to become enough populated to be harvested, and then they should be harvested in quantities which does not weaken them. By harvesting, it is said they can become stronger though.
There are invasive non-native plants that people are happy are weakened. When invasive plants take over, its understood they need curtailment. Some of those invasive plants are feeding local fauna, and so the plants should be slowly curtailed, until local food sources reemerge? Or opt for quick eradication of flora, relocating fauna temporarily, to be followed by the re-planting of native plants, that flourish without any competition. By the way, it is said, animals do not relocate well. So, this is possibly impractical. What if a plant is doing fine next to the invasive plant. What if the invasive is filtering a stream into a forest, where otherwise there is no native filter that grows? What if it is helping out a native plant, bringing up nutrients? In general, non-natives are not helpful enough given the need to hold native flora and fauna together. Some are helpful (considered species by species). Even if helpful, if they become invasive, they are not.
Hopefully in this day and age no-one would eradicate native plants. Or so one would think. Hemp of course being an example of a plant once eradicated from the landscape, except perhaps on medicinal company land holdings and greenhouses. Which gets to be a bit anthropological. One might ask, what is the background of the companies , owners, employees? (see anthropological work by Dan Rose for an example). By deriving chemicals from plants, plants are valuable. By deriving chemicals from plants, and then manufacturing those chemicals without any plant harvesting, plants might be devalued as the chemistry replaces the plants – both culturally, and monetarily, conversely making the plants more widely available and valuable as an affordable resource. So making chemicals industrially given pressure is taken off of wild plants, helps maintain plants in the landscape, and maintain landscapes, as the plants then do not need as much harvesting, assuming a vital and strong interest in native plants continues.
The thing is, that plants are reliable and nutritious, but as they are living beings, with variable chemistries due to soil, water, nutrition, and more – so on the plant side, some outcomes might vary, as the plants will differ somewhat. Being planted in soil also makes plants even more incredible and healthgiving.
Knowledge for all health practitioners is accumulated.
Overcollecting native plants limits the healthful future of many people, and limits employment. What if there is an extreme need to collect a plant, but almost none left? Maybe that is why people say to take half of what is there – so that in extreme need, a person can collect even with few plants available, without extreme guilt (which would be unhealthful). Or perhaps the point in saying take half, is collective imagination powering reality – as if saying that half is always available is the same as saying one last plant will never be reached; that is, by stating “half” so that the collective human will, will cause creation to be plentiful.
If a (drug) manufacturing company is created to take pressure off woodland plants, that is great. (Probably also great if somehow shoe manufacturers could take pressure off of woodland floors – maybe harvesting without shoes or in moccasins is safest for the woodland, if the foot is already adapted to help woodland plants). Hopefully no drug company would feel compelled to maintain control over the market both on the shelf, and in the woods, if both a plant, and a manufactured drug can do some of the same things. That would be counterproductive though, in terms of public and employee good will. Hopefully good instincts and morals prevail. If the plant is invasive, helping eradicate it might seem only positive. As previously mentioned, how best to do so, and on what schedule, might not always be clear. Such as if locust trees invade, bring up nutrients, and over time, are anyway replaced by a native tree happy the locusts came before them perhaps. It needs to be said though, that once people ask chemical industries to solve a problem, if later they then ask them to do a 180, that change might not be quick in order to not lose those companies, companies that support employees, and sometimes places with plants.
Though collecting of plants is great – over collecting should not happen, or it might be said that no native plants should be harvested in order to preserve planted and wild landscapes, and yet, it might be harvesting plants that helps plants grow. Plants should not be compromised, but neither should individual animals and humans, and gathering humans, humans that gather and eat and heal be compromised from practicing such culinary and home arts.