WELCOMING THE WEEDS
FARM LIKE AN ECOSYSTEM PART II
A weed is a plant that has mastered every survival skill except for learning how to grow in rows. Doug Larson
July's rain was biblical; drenching, field-and-basement-flooding rain. In midsummer, lush green moss grew on the trees, on the old walls, and on the cobblestoned walks. The fruits of my labor were beyond prolific. The chickens and ducks feasted on the extra salad greens, more than they could eat. The heavy rains meant that plummeting mulberries gave way to plummeting cherries. The donkeys were deliriously happy (and fat) with the enormous growth of field grass. I regretted that I did not eat snails—nor would the chickens—as there were enough cruising the gardens all night to feed us for an entire month. Living in the mountains, most of the water poured off the land into spontaneously-generated ponds. It filled our cisterns, our wells, and finally the river which quickly overflowed its banks. Enough water for everyone in our province to store and irrigate for months. The rainfall took out whole sections of our single lane dirt road, piling the mud from the hillsides into the middle of our only way into town… along with wild grasses, twisted crops and a jumble of shrubs, roots, and rocks. Clearing it took only a few days. What concerned me were the now heavily eroded hillsides bordering the flooded fields. These hedgerows which were washed away were essential, providing food and shelter for a wide range of wildlife which partnered with our farmers. Where would the soil and the plants come from to repopulate the borders?
After the deluge
I shouldn't have worried. The submerged fields and the eroded hillsides were dotted with local wild plants within weeks. It was a graphic reminder of the regenerative power of nature and a lesson in succession ecology. Whenever there is an opening in Nature's tapestry—as soon as any soil is exposed—the most resilient local plants move in. This year, when two months of record-breaking heat followed the rains, these resilient weeds were still multiplying, covering the exposed ground. By late September, the hillsides were once again restored to green - not yet a solid green, not yet hedgerows - but on their way.
Three months later
The first plants to re-colonize a habitat are called opportunistic weeds. In specific ecological terms this re-wilding is called secondary succession—when pioneer plant species return to an area following a disturbance. There may have been a flood or a forest fire which devastated the immediate ecosystem... or plowing a field. These plants are critical in rebuilding both the communities below and above the ground. They are the first to arrive on the scene because they are flexible about their growing conditions. They are not fussy about the amount of moisture, soil type, or fluctuating temperature available. They grow rapidly and are quick to germinate. Their seeds are often small and easily distributed by the wind. Once they have gotten their roots into the soil, they have the ability, even under stressful conditions, to take up large amounts of nutrients. They are tenacious, holding the soil from erosion, retaining moisture in the ground and improving the soil quality. The pioneer plants sequester CO2; without them, the soil is no longer a carbon sink. It is their job to restore biodiversity to a devastated ecosystem—to heal the literal earth—and prepare it for the next migration of larger, slower-to-colonize, more deeply rooted plants and tree saplings. Within a few months—it is now November—plants have blanketed the entire hillside erasing most signs of the mudslide just four months ago.
The first three pioneer plants to arrive on the eroded embankments along our road were all hardy natives to central and southern Europe—but they can be found on every continent. Long ago they were incorporated into the diets of indigenous peoples and herbal medicine practitioners in the area. And they are still valued where I live—central Italy mountain country. The local plants are collected by weekend foragers who remember the soups and garlic-sautéed vegetables of their grandmothers. It is not without some irony that I am reminded of my Maryland neighbors weeding out just those plants which my current neighbors collect for dinner.
It’s at this point that I need a disclaimer, though I would love to write about the benefits of so many of our weeds as effective medicine. But... I cannot advise or recommend plants for medicinal or health use. Please consult a health care provider before consuming a wild plant for food, medicinal, or health use.
Sow thistle
Sow thistle, Sonchus oleraceus, above, was the first to arrive in the wasteland of mud. (Because many common plants have the same common names I use the Latin genus and species to describe plants.) It can tolerate almost any soil condition. Typical of all the pioneer plants, it is invasive only on bare or disturbed ground. (Bare ground, meaning the lack of other vegetation, seems to be the requirement of many 'weeds'.) Sonchus, which the locals call it, is an old-time culinary favorite; all of it: the young leaves, flowers and roots are all edible. Much like other chicories, the roots can be roasted and used as a coffee substitute. But it's the leaves which are valued by the mountain dwellers (and browsing animals, wild and farmed) as a mineral-rich vegetable. However, I am attracted to its free medicine. Traditionally used for stomach ailments, there are promising studies, just this year, on its’ potential medicinal properties.
Clematis and blackberry
The second plant to show up and take root was a local clematis, Clematis vitalba. It is found worldwide on degraded areas because it is not fussy about soil conditions. Though written about as an invasive species, it is considered a minor weed in my region and does not impact cultivated areas, perhaps because almost as soon as it begins to expand its horizons, it is outcompeted by the local blackberry vines which farmers and foragers alike encourage. (In the photo above, the clematis is the one in flower. The darker stems belong to the overtaking blackberry.) It is an important food plant for pollinators and, when blooming, is a real beauty. Among certain herbalists and homeopaths, it is the equivalent of valium and used as a calming remedy. As such it is one of the five ingredients in the Bach Flower Rescue Remedy.
Oxtongue
The third plant was bristly oxtongue, Helminthotheca echiodes. (Above) It is found along roadsides and field margins. Though I have friends who avidly collect it, even with lots of garlic and excellent olive oil, I would have to be very hungry to stir fry the thorny pock-marked leaves. Additionally, this plant favors the most unsavory habitats. Yet, it too is being studied... for potent antioxidant, antimicrobial or anti-inflammatory properties. Currently there is great interest in the wild, traditional Mediterranean plants for both their nutritional and medicinal benefits.
Pioneer plants, in addition to appearing on disturbed ground, are also found on land commonly called waste areas: the margins of fields, along roads, highways or clay banks, possibly in the parking lot of your local market, and—where I live—around the village recycling bins. They are the welcoming committee, modifying the environment as soon as they put down roots, providing more enticing conditions for the establishment of less devastation-tolerant plants. But once they jump start the ecosystem, they don't hang around—and I have never had them overwhelm my gardens or had the need to eliminate them. They enable the plants of the climax community (the end point of a succession sequence) to become established and then they are outcompeted. By definition, climax community species inhibit the proliferation of plants from earlier stages.
On my road, where the later-succession plants have made themselves at home, the opportunistic plants are gone. After the greening of the banks of eroded land, the blackberries and elderberries and other woody plants moved in, crowding out—and shading—those first herbaceous weeds. Later, saplings arrived, primarily oaks but also maples, ash and evergreens. Even the young saplings can hold a very steep hillside from erosion and mudslides. (Above.) Where the hedgerows of blackberries dominate, where there were established trees, there was no erosion from the July storms. But where field grasses had taken over - and particularly where the local government cut back the grass as part of road maintenance or the edge of the road was clear cut - there was major devastation.
To do battle with these weeds is a mistake. We blast them with herbicides in our fields or spend our free time digging them out of our gardens. The irony is that the herbicides only increase the resilience of the wild plants, which, in many cases, are developing evolutionary strategies to the combined bombardment of climate change and deliberate poisoning faster than our genetically manipulated food crops. These are settlers, early arrivals, not colonizers. They are showing us how to save and resurrect our damaged ecosystems. They are not competitors as much as they are doctors without borders.
WEEDS AS SOIL INDICATORS
Chickweed
Long before soil test kits, before there was the local agronomist or farm agent, farmers observed their soil before they planted. They learned to read the trees and shrubs and local weeds. Every environment has its’ own community of aggressive weeds which move into disturbed ground. Every plant has a range of conditions in which it can germinate, survive, grow, and reproduce - with the range narrowing with each developmental stage. I had to learn taxonomy in school. My neighbors and friends learned the plants from their grandparents; what was edible, what was medicinal (and occasionally toxic), and how to prepare it. A patient neighbor taught me the local plants and once I could put names together with their flowers, leaves, and roots, I let the plants tell me about the land on which I was living. One plant may have a wide range of conditions it might tolerate but three or four plants growing together give a clear indication of exactly what is going on in the soil. There are lists and charts of indicator species to be found in books and on the internet. They are quite specific and include salinity, degree of soil compaction, high or low mineral levels, nematode infestation... However, as I often write, I rely more on local old timers for local plant information than any other source. The public library, the local agricultural college or agricultural extension agency is a full of free information but it will not be as specific as what a long time resident knows.
When we first cleared the rock and rubble for our gardens, plantain, Plantago major, popped up everywhere, as it does on compacted soil. As each new garden became productive with increased soil fertility, chickweed, Stellaria media, and chicory, Cichorium intybus, moved in forcing the pioneer plants to a narrower niche out along our road. Though European in origin, most of the common weeds are now found throughout the world. When I say that my soil is blanketed with chickweed and chicories, no one knows that I am bragging. These two plants tell me that I have a balanced fertile ecosystem perfect for growing most of my vegetables. The chickweed could easily cover our gardens—and it would not be a problem—it is much in demand for salads, for poultices, for tinctures and for the chickens.
WEEDS AS SOIL PROTECTION
When an area is devastated by plowing, erosion, fire or flood, if the surrounding ecosystem remains intact, the system repairs itself via those first responders. But it is essential that the hedgerows and road edge plant communities survive. They are the seed banks. In summer, they provide the plants which keep the land covered, lowering the soil temperature and holding moisture. But just keeping the soil covered is not the same as keeping permanent roots in the soil. Mulching with dead plant material may hold onto some moisture already in the earth, but during dry periods, a thick layer of mulch will absorb the scant rainfall, impeding it from penetrating the soil. And a deep layer of mulch will discourage self-seeding from plants I want to encourage. The pioneer plants provide living protection and immediate stabilization while improving soil quality. And with roots in the soil they jump start the interconnections with the soil biome.
I WANT THESE WEEDS
The bottom line is that I want these wild plants. I need these plants, both the pioneers as well as the later succession plants. The wild plants in my gardens, those with taproots—like dandelion, chicory, burdock and wild carrot—sink their roots deep into the soil, drawing up water and minerals. In an area with a rapid increase in forest wildfires—and is there any area which is not at risk from fire—the older perennial weeds with deep taproots, much like the old mother trees, may survive the fire to regrow. These plants are also community builders along with the tree roots, the fungus, the worms, and the myriad microorganisms which trade resources in the soil. The deep-rooted wild plants are an essential part of the complex food web in the soil as they mine and store and share essential nutrition. And, like many of the wild plants in our fields and gardens, they are also important vegetables.
Where are your weeds? a new apprentice often asks when they first see the gardens. I laugh because they can't see the forest for the trees. They see thriving plants everywhere; what they would call weeds have been incorporated into the gardens and the fields. Living in a robust community of diverse plants and rooted in rich soil, the wild ones have grown green and healthy, producing abundant and beautiful flowers. The wild ground covers: chickweed, purslane, the plantains, lamb's quarters, clovers and margeritas (above), shepherd's purse, goosefoot, red pigweed, wild arugula... the list of wild edibles is endless—create a blanket into which I plant my vegetables, herbs, shrubs, brambles and saplings. I harvest them daily for our salads and whatever we can't eat goes to the animals. I have learned that when burdock, Arctium lappa, appears I must leave it where it has settled. Its long taproot makes an excellent vegetable and a medicinal tincture. To disturb the plants when they finally settle in would be a mistake for they have found exactly the place in which they will prosper. For several years I had to beg stinging nettles, Urtica dioica, from friends and wildcraft it as I could not get it to grow in my herb garden. Eventually, after numerous failures, I planted roots from along the river, with a heaping amount of its surrounding soil, in several places in the vegetable garden. The nettles prospered only in one patch and I left them where they were happiest.
Motherwort
Many of the wild plants which just show up have medicinal uses. Some, like Saint John's wort have strong double blind studies backing up their eficacy. Many prefer the company of their own kind and spread out from where the conditions are supportive. Motherwort, Leonurus cardiaca, another gorgeous weed belonging to the group of spontaneously appearing medicinal perennials, has become lush in a bed of compost. Peer reviewed studies have found “a complex biological activity, with cardioprotective, antioxidant, antimicrobial, anti-inflammatory, analgesic, nephroprotective, and antiviral properties, among others.” Yarrow, feverfew, mullein, mugwort, vetch and many others, spread via underground roots or just drop their seeds right where they are standing. They insert themselves, quite happily, within the garden's and fields, just enough to cover all the bare ground, but coexisting with any of the crops. In late fall they die back to their roots, leaving plenty of space for the winter vegetables.
I can take control of what is growing when needed. In general I eliminate almost nothing in the gardens, though I do move some plants around. Knowing the conditions each of my plants want has been critical. (No, I don't remember them all. I look them up.) And knowing what any aggressively spreading plant needs can help manage it. Sometimes it is enough to cut off the flower heads when they appear but it also helps to know what nutrients or pH are critical to their survival. By altering those, I can contain a plant's growth or spread. I add compost or composted manure to the base of each hole when I plant the vegetables and fruit bushes rather than spreading it everywhere. I fertilize the trees at specific times—and only under their drip line—avoiding spreading manure over an area with wild plants I want to contain.
It is important to mention that bees—as well as many of the equally important but less-discussed pollinators—rely on many of the common weeds for their food supply. I call these plants the come hither plants, as they lure the pollinators to my gardens. Because of extreme habitat loss as well as intense monoculture farming, weed flowers are quickly becoming an essential food resource for pollinators.
Purslane
I have used a mix of salad herb seeds as living mulch around summer vegetable plants. But this summer, there were torrential July rains and these tender greens were almost wiped out by a flotilla of slugs. The tomato plants were left with exposed soil surrounding them and had to fend for themselves when the summer turned very hot and dry. But the plants which were surrounded by purslane, Portulaca oleracea (above) a world wide weed and juicy veggie raw or cooked, thrived. Now, with monsoon rains again, the onions and garlic, fava beans and cruciferous veggies are being planted into a mix of wild chicories and wild arugula. Due to my own inattention, I missed the arrival of the cabbage moths when they left their eggs on the underside of the leaves. The leaves were chewed, but only a few at the top. Amazingly, almost no larvae grew. I am wondering what allelochemicals are being produced by the wild plants; if the living mulch was such obnoxious company they discouraged the larvae. The more naturally occuring herbaceous weeds are far more robust and resilient (or simply more repulsive) to predators than a mixed bag of cultivated greens.
Scotch broom
There is always the inevitable question, which follows my rant about having weedy gardens... but don't these weeds take over? Yes, perhaps, if I were growing a monoculture with wide bare paths between the rows, large enough to accommodate tractor tires. But weeds do not take over in small-scale biointensive farming. In a vibrant ecosystem of perennials and annuals, of mixed woody and herbaceous plants, there is (almost) nothing which arrives which is not welcome. Only once have we had a plant which had intentions of being invasive... scotch broom, Cytisus scoparius. (Above) In the pasture and the hay field, it must be cut down to the ground just before it flowers. However, it makes beautiful rustic brooms and excellent kindling and is a stunning plant holding the hillside along the road. Ironically, it has never appeared within the food gardens and its love of sunlight keeps it out of the forested areas.
In the field and garden, the opportunistic plants are literally and figuratively the ground breakers. They move onto bare space where there is no competition. But the process of moving to a climax community involves constant change. The community itself is stable but the species composition (which includes insects and animal life) varies, more so now with increasing climate extremes. And the plants will continue to change with the environmental changes.
A WEED IS A PLANT GROWING IN THE RIGHT PLACE
Wall rocket
Driving into the city, I pass a large field where sunflowers are grown all summer. Then the field is plowed for sowing late winter wheat. In spite of the earth being stripped bare, in early December, the entire expanse is a carpet of white wall rocket, Diplotaxis erucoides, a wild brassica. (Above) Rocket is another of those first responder plants which arrive after ecosystem devastation. The raw young leaves are delicious in a salad, with a stronger kick than cultivated arugula. The older leaves are savory when stir-fried in olive oil and garlic. Though rocket had been foraged for centuries—and later considered a pervasive weed—there is now a conversation within the sustainabe agricultural community about cultivating it as a crop. I got out of the car to look at the rocket. It was so thick and lush—and with no hedgerows around—I wondered if some wise farmer had planted it as a food crop.
I read articles daily about saving the old seed lines of grain crops for future breeding and shudder at the energy waste (fossil fuel and human) needed to preserve something in deep storage which may no longer be viable in the coming climate. Why are we not utilizing what already works; plants/weeds which are incredibly resilient and evolving with the changing climate? Volunteer plants like wall rocket quickly adapt to the changing air, water and soil conditions. Studies are underway which may (finally) demonstrate that our standard weeds show more resilience and greater adaptation to rising temperatures and concentrations of CO2 than our standard crops. They kick start rebuilding any damaged ecosystem with the incredible bonus of being nutritious and medicinal, not just for us but for numerous species. They are pollinators. They are survivors... still standing, thriving, after millennia, without our intervention. Our weeds are just where they belong, in our fields, along our roads, in every compromised, degraded, or devastated ecosystem. Free food and medicine in our backyards. Essential for ecosystem restoration, perhaps they will also be essential for our future food and medicine.
I want these weeds.
Here are a couple of sites with excellent photos of indicator weeds with which to begin:
https://www.almanac.com/what-weeds-tell-you-about-your-soil
https://plantura.garden/uk/gardening-tips/plant-overviews/indicator-plants
https://duckduckgo.com/?q=what+do+weeds+tell+you+about+soil&t=osx&ia=web
And here are a few articles I used for information on research being done on the benefits of weeds as food and medicines:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10489745/
https://www.hindawi.com/journals/ijfs/2022/4181656/
https://pubmed.ncbi.nlm.nih.gov/21793765/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6500680/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7911030/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8704218/
https://www.sciencedirect.com/science/article/abs/pii/S0304423819306648
In a previous lifetime, Zia Gallina worked as a botanist for the National Parks Service, on the C&O Canal outside of Washington D.C. (lecturing on wild indigenous and naturalized medicinal and culinary plants). She was also an adjunct professor teaching biology and environmental science at American University, Washington D.C. But she has always been, first and foremost, a farmer and a champion of small-scale biointensive farming, tagging behind Mother Nature, trying to stay as close as she can get.
