Tag Archives: Foraging

Collecting wild plants for gardens: how to forage responsibly

If you like gardening and native plants like I do, you know there are some mixed messages about collecting wild plants. We hear growing native plants is good, but only if they come from reputable commercial nurseries. We’ve learned the harms of picking a wildflower, but give little thought to building with wood, meaning somebody harvested an entire tree from a forest. We understand hunting and fishing is legal with a permit, but what about plants?

Of course concerns about proper use of wild spaces are well-founded, but you’ll come across a confusing mix of sentiments. Since native plant enthusiast communities are typically pretty pro-environment, sometimes it seems like those who want to make the tiniest impact bear the most scrutiny.

The truth is, all cultivated plants came from the wild at some point. And there are many benefits to getting more diverse and more local plants in our gardens than what nurseries currently offer. To do that, we need to learn the legal, respectful and ethical ways to collect wild plants.

Your resources: the Bureau of Land Management, Forest Service and U.S. Department of Agriculture.

If you live in the United States, there are several federal agencies to help manage public resources and wild plants. They provide information and guidance for free, since working with the public is part of their mandate funded by taxes. BLM land is by far the easiest to collect on, and depending on what you’re going for, hobbyists may not even need a permit (though ethical principles still apply). National forests also exist for managed harvesting and allow regulated collecting by the public. Collection permits cost as little as $20.

If you plan on traveling large distances with plants you collect, such as from Hawaii to the mainland, you can seek guidance from the USDA.

Know what kind of plants you’re looking at

In some parts of the world, poaching rare plants is driving species to the brink of extinction. Some of the most common targets are carnivorous plants, certain cacti and succulents, orchids and bulbs. Their unique shapes and features make these plants stand out, and slow growth makes them hard to propagate, so nurseries can’t keep up with demand. Unfortunately, their slow growth also prevents wild populations from recovering from constant harvesting. Before you disturb wild plants, identify them well enough to be sure you’re not threatening any vulnerable populations.

On public lands where collecting wild plants is permitted, the National Forest Service or BLM will provide vulnerable species lists. But even if you are on private land with permission from the owner, it’s better to leave vulnerable species intact.

Harvest seeds or cuttings rather than whole plants

When a plant is producing seeds, the least disruptive collection option is to harvest a few seeds and leave the plant intact. If there are no seeds, a small twig or stem cutting lets the plant recover. If that’s not an option for the species, consider taking a basal cutting—a rooted stem or shoot from the base of a clump-forming perennial—without digging up the whole plant. All these methods reduce the need to deprive the area of a whole, healthy plant.

Artemisia ludoviciana cuttings, prepared from a single stem, cut into segments and prepared to be stuck into a rooting media.

Collect only the plants you can keep alive

Another reason to ID plants you want to harvest is to be sure it’s a species you can propagate. It’s wasteful to start digging at unidentified plants only to discover they have deep taproots you’ve broken off and doomed the plant. Trying to collect wild plants you don’t know how to transport or grow can lead to waste as well. Be sure you have a field guide, access to a digital database, and a cooler or container to keep cuttings cool, protected and humid for the rest of your trip.

Keep a light footprint when collecting wild plants

Evaluating a prospective collection is about more than that individual plant. Survey the other plants of that species in the area. If you see other signs of collection, move to a new area. Make sure there are other plants of the same species around. (The rule of thumb is to not collect more than 5 percent of the plants in a small area, or 1 in 20 plants.) Don’t take the largest or healthiest individual, and don’t take the only seedling if there aren’t several other seedlings nearby.

My own advice: don’t overlook common and non-showy plants

There’s no doubt that a cluster of native wildflowers is a lovely sight. Most wild plants taken into cultivation as ornamentals are the showiest species, then bred to be even showier still. But if your gardening goal is to widen the domain of the ecosystem and to invite birds and insects to make use of your land, the keystone plants—the ones that are so abundant and dominant that they define the ecosystem’s boundaries—are valuable to incorporate.

These wild-collected whiplash daisies, cool-season bunchgrasses and artemesias are from a private property with permission. None are rare or showy, but I think they are appealing in combination—something to keep in mind collecting wild plants.

Importantly, plants that don’t bloom brightly or tower above the others are underrepresented in native gardens. Depending on your region, that could refer to prairie grasses, sagebrush and other artemisias, rabbitbrush, milkweeds, sword ferns or others. It’s a challenge, but also a great benefit, to incorporate these plants into your garden—to evoke not only the floral color but also the texture and character of the wilderness.

A garden of Colorado native artemisias and grasses, with just a few native flowers scattered in. This will form a handsome naturalistic texture when it fills in.

Bringing tropical cuttings and seeds to life

If you love plants, coming home from a trip with a bunch of seeds and plants in tow is like adding an extra day to your vacation.

All but a single one of these bags was approved at the USDA checkpoint to travel from Hawaii to the mainland, since the U.S. government is primarily concerned about the risks of transporting pests contained in commercial crops and fruit. As tropical plants washed free of soil, pulp, cotton, leaf spots and bound for a quarantined indoors setting, there’s little risk that any would become invasive threats in Colorado’s snowy climate.

Like an 8 year old back from trick-or-treating with a cache of Halloween candy, you spread your bounty out over the kitchen table and sort through what you got. After making some quick strategic plans, it’s off to the local garden store to buy some extra seed trays and plastic domes to get started.

Out of the dozens of types of plants I got though the USDA inspection in Hawaii, I feel relatively confident I can grow all but few. The philodendron vines and Monstera are notoriously easy to propagate from stem cuttings, even in plain water. I have two types of Crinum asiaticum (spider lily) seeds, which I’ve grown before and know they’re basically foolproof. Croton cuttings are also fairly easy to root in soil or water, although one of my cuttings is looking pretty wilted after shipping and I’m not sure if it will make it.

A batch Crinum asiaticum, or spider lily, seeds planted in a simple seed tray in vermiculite and potting mix. These are very easy to sprout—I figure all 6 out of 6 will survive.
An African tulip tree in Kona covered with flowers and big pods full of seeds.

One species I’m less sure about are the Spathodea campanulata seeds, known commonly as the African tulip tree, which reportedly have low germination rates. The pod I found on a tree growing next to a parking lot in Kona contained what looked like thousands of seeds—a dense, loose mass of flat, lightweight seeds, each imbedded in a thin cellophane-like sheet of tissue. Even the slightest breeze scatters the ultra-lightweight seeds into the air, where they flutter around like mosquitos. (This was an annoyance to the group I traveled with, when a swarm sparkly seeds blasted out of the pod on the dash and into the cab when the air conditioner came on.)

The seeds are plentiful and extremely gregarious travelers, but this plant’s reproduction strategy to is to produce its seeds en masse and allow them to spread far, with lower emphasis on each one’s viability. I’m worried there’s a chance the entire batch dried out too much while it was still on the tree and none will sprout.

The seeds of the African tulip tree are extremely lightweight and plentiful. This bag of seeds came from a single, banana-shaped pod. Although the seeds have a relatively low germination rate, it’s easy to see how Spathodea campanulata has become such an aggressive invader in tropical forests where it has been introduced outside its native range. These are headed to a seed tray to see if any will sprout, and will remain indoors as houseplants if they do.

I’m also less sure about the single, grape-sized seed pod I found in a refuse pile in the Maka’eo walking path garden at the old Kona airport (an amazing garden to visit if you are ever in the vicinity, by the way). I thought I knew what it was—I initially thought it was a Euphorbia neohumbertii—but now I’m looking that species up and having some doubts my ID was correct. In any case, the three seeds, which fit snugly in the three-chambered pod and have hard casings that resemble pine nuts, seem like they might be temperamental when it comes to watering the right amount. (An aside: these gardens are amazing place to visit if you are interested in looking at a wide range of tropical plants and succulents. But, though the gardens are unguarded, please don’t pluck any attached plant parts or take out any fallen fruit or other useful material. The gardens are maintained by local people, and theft of valuable plants and food crops has been a problem there).

Finally, I have some seeds from an Aloe of some sort that was absolutely covered in open pods, and a sandwich bag of seeds rom a large planting of Stapelia (also known as “carrion flower”) in Kona that was spewing its cottony fluff all over the sidewalk and beyond. The Stapelia pods look remarkably similar to those of milkweeds, as do the seeds themselves, so I looked the genus up and found Stapelia comes from the same subfamily as milkweed, Asclepiadoideae.

A mound of Stapelia, or carrion flower, growing at the community garden in the old airport in Kona. It turns out, Stapelia is in the same family as milkweed.

(It’s fascinating, the connections you can make when you know a bit about taxonomy. You can walk into a new environment, knowing hardly anything about the plant species there, and quickly identify a bunch of plants with Google by searching your location + the plant family or genus a specimen seems to belong to).

In any case, I have never grown Aloe nor Stapelia from seed, and sometimes these drought-loving plants can be temperamental to water properly in shallow trays. So we’ll see what happens.

I’ve been fascinated by the seeds from a Delonix regia tree, also known as royal ponciana or flame tree. Coming from an enormous dangling pod, which I left in Hawaii to reduce the risk of carrying pathogens, the seeds look like elongated beans. But unlike beans they come in a waterproof, waxy casing that prevents them from swelling even when soaked in pure water. It’s a strategy many plants and trees employ to encourage their seeds to last longer before they sprout, which gives them more of a chance to spread far and wide or emerge at the right times.

Many varieties of Lupine have a similar seed coating, which makes sense because they are also members of the Fabaceae or pea family, and this is something that can make their propagation more complicated. In the case of Lupine, the translucent seed coating is degraded by winter freeze-thaw cycles, fire, or long periods of time in general, helping the plant to get at least some of its seedlings to lie dormant in the seed bank and spring up in optimum conditions in early spring or after a wildfire clears competitors away. But Delonix regia, a tropical species, doesn’t live with cold winters or with recurrent fire (as far as I know). Instead, I wonder if the casing naturally dissolves in the stomach of an animal or bird, and sprouts great distances away in piles of poop.

In any case, I set seven seeds to soak in a tray of water and none of them looked any different after 24 hours. As a test I scoured the corners of two seeds with a piece of sandpaper, and sure enough, they began swelling from the scoured end, stretching and ripping the waxy coat apart until the entire seed had swelled.

Delonix regia (flame tree) seeds soaking in water. The two larger seeds were scoured at one end with sandpaper, allowing the seed to swell with water and break out of the waxy waterproof coating. The rest look exactly like they did before they went into the tray.

I’m also unsure about the viability of the Terminalia catappa, or sea almond seeds, which were easy to find all over the beaches in Hawaii. Supposedly these too are fickle to grow from seed—many of the seeds cores rot out during the long time that passes between the moment they fall and when the right conditions come along to germinate. The interestingly almond-shaped, lightweight, corky seeds evolved to float in sea water and colonize distant beaches, but are hard to pry open and I was unable to cut any open with the tools I had on hand during my trip. I’m excited about the seeds because the attractive, large-leafed trees seem to be a potential substitution for fiddle leaf figs, which are extremely trendy houseplants, but, in my opinion, are not well suited to life indoors. Fiddle leaf figs are just too finnicky, languishing in the low-light conditions in most homes and developing unsightly spots or dropping leaves at the slightest provocation.

Clusia rosea is another candidate I hope to use to fill the role of the fiddle leaf fig, and I got a few tiny seeds along with some cuttings. The seeds are small and come imbedded in a sticky orange goo that helps them attach to mature trees in a wet forest, germinate on a branch, send aerial roots down to the ground and ultimately overwhelm or strangle the unfortunate host tree. The seeds dry out and die easily (I planted six and the rest were dry and dead within a day), but the cuttings seem resilient, staying very plump and green in transport.

Additionally, there are some dry Pandanus tectorius (screwpine) seeds in my cache, a rare Hawaiian native plant that happens to be extensively cultivated, and I was able to collect the dry seeds from the lawn at a resort.

I’m fortunate to be somewhere with a lot of light, and the plants are getting started in a humidity dome to help them root and also give me a chance to discard any that show signs of flies or disease. However, they’ve all been rinsed and soaked, plucked and preened, and have had any spotted or damaged leaves removed. I’m not expecting any problems, and can’t wait to see what some of them turn out like.

A cutting of Clusia rosea, or autograph tree. I have no experience with them but I think they will be very easy to root because the cuttings are still plump and green with no wilting even after days in transport.

Botanical tourism: bringing plants from Hawaii to the mainland

When I was a kid, my dad sometimes brought me bits of plant life from his work trips around the country. I was more interested in those kinds of souvenirs than anything from an airport gift shop.

They were nothing ecologically-sensitive or fancy. Just nuts or seed pods from trees in a public park, or sprigs of foliage from a buffer strip along a parking lot. I remember a husk of horse chestnuts from Washington DC, a handful of Agave bulbils from San Diego, and lots of pine cones.

It turns out I now travel the same way. But unlike my childhood gifts, which I usually dried and arranged on what I dubbed the “science shelf” in my bedroom, I’m more interested in things I can propagate. I find that having a story behind my houseplants gives me a deeper interest than just buying them at a garden store.

So, on a recent trip to the Big Island of Hawaii, I took the opportunity to collect some really interesting and beautiful plants, with the added challenge of following the stricter regulations of traveling over an ocean with cuttings and seeds.

Me and Jeff on the Big Island
Jeff (holding the camera) and me on a trail on the Big Island

Traveling eco-safe with plants

Over the years we’ve learned more about the risks of moving living things around the world. Every day, millions of tons of timber, grains, livestock, plants, flowers and produce are shipped across the oceans. Many have escaped into the wild, becoming invasive species that overrun native ecosystems. Others harbor hidden pests that could wipe out species or destroy agricultural industries. Consider the American Chestnut, a once-dominant North American tree that was wiped out a century ago by an exotic fungal disease, or the emerald ash borer, a bug from Asia that is steadily eradicating North American ash trees.

As much as I love collecting plants, it’s important to me to do it safely and legally. I would hate for my legacy of life on Earth to have been personally responsible for destroying a species. So I follow the regulations and take some additional precautions. That also means being above-board with the USDA and any other relevant agencies.

Safe vs unsafe plants

Living in Colorado, it’s unlikely a tropical plant brought from Hawaii would survive outdoors and become invasive. These are strictly to become houseplants, isolated from the local flora. But that’s not the case if you’re in a balmier state, like Florida, Texas, California, or even marginally similar places like Arizona or Oregon, so there will be stricter considerations than what I describe here.

A few categories of plants contain species that are remarkably adaptable and widespread, and the U.S. Department of Agriculture prohibits their transport entirely. They can also harbor viruses, fungi or insect pests that can more easily jump from one climate to another. That list includes grasses, sedges and cacti, as well as most commercially-important vegetables and fruit. In the case of cacti, an extremely destructive cactus moth was brought to Hawaii to eradicate an invasive Opuntia species, burrowing deep into the flesh and eating it from the inside. The moth could put several North American prickly pear species at risk.

Plants must be soil-free

Moving soil is a concern unto itself. A handful of wild soil can contain hundreds or thousands of species bacteria, fungi, viruses, insects, worms, nematodes, slugs and snails or various pest eggs. Some of these species may not even be documented by science yet, and it’s likely there are organisms there that can live in both tropical and cold climates. Due to the incalculable risks, moving soil into the U.S. mainland from overseas is banned entirely. Plants need to be bare-rooted and washed, or better yet, restricted to dry seeds and soil-free cuttings. Potting media, which is an artificial product made of pasteurized dead plant material and fillers, is not soil, and that’s what nurseries cleared for shipping to the U.S. will use.

My experience collecting plants in Hawaii

Hawaii has an impressive variety of landscapes and microclimates. In the rainforest biomes, you can really get a sense of the risks posed by invasive species when you realize that almost all the trees and vines growing there came from someplace else. From the dominant eucalyptus trees to the ubiquitous pothos vines, the wettest zones are basically a hodgepodge of aggressive plants from jungles around the world. The ecosystem there is basically a brand new assortment of organisms, and we’re yet to see how it develops over coming generations.

This jungle on the Big Island’s northwestern coast is captivating, but most of its plants come from elsewhere and have overwhelmed the native species.


The resorts and villages, meanwhile, are manicured collections of what I basically think of as houseplants. The giant banyan trees, with curtains of aerial roots dangling from the branches, come from a group of Ficus tree species that grow in the wild by sprouting from seed on branches of mature trees and eventually smothering them with their roots (strangler figs). They include the familiar “weeping fig” and “rubber tree” which we know of as houseplants. There are hedges of hibiscus, beds of crotons and bromeliads, Monstera vines climbing the trees. There are Sansevierias and Heliconias. Aloes and Agaves. Everything you’ve seen in your local nursery’s tropical section is now here, giant-sized.

And that’s where I got almost all of my cache. The gardeners coming through to trim the plants on practically a daily basis provided lots of cuttings, and the seeds scattered around the ground made good finds. Tropical trees tend to be heavy seed producers and nearby sidewalks and streets are littered with them.

Whenever I found a cache of seeds or downed branches that looked appealing, I looked the species up to make sure I thought I could grow it at home. Before the week was up I compiled a cooler’s worth of seeds and cuttings, bagged, labeled and ready to go.

Going through the USDA checkpoint

Getting live plants to the mainland is an intimidating thought, given that you can’t even bring an orange for lunch onto an airplane headed to North America. But the regulations are there to prevent specific pests from getting across, and due to the millions of pounds of commercial food crops shipped around the world each year, some of them have unfortunately already gotten to Hawaii—but some have not yet reached the continental U.S. Others have reached the continental U.S. but aren’t yet in Hawaii, so restrictions go both ways. Additionally, there are a lot of pests that hide in fruit in particular. If you want seeds, which are less hospitable to stowaways, just make sure to scrub the flesh off and put clean, dry seeds in a package for inspection.

Cuttings and seeds are cleaned, dried, bagged, labeled and ready to go through USDA inspection to bring to the mainland.

Cuttings are, similarly, surprisingly easy to bring. As long as they don’t come from a list of prohibited plants (which includes plants in the citrus family, cacti and grass), and they’re not endangered (which they wouldn’t be because I only collected cultivated plants), they’re likely permitted.

In this case, you want to remove any leaves with bruises or spots that could potentially harbor disease. Luckily, many tropical plants are vigorous enough that they can grow from a segment of stem without any leaves at all.

It’s probably important that you are able to identify the species you are working with, in case the USDA agent doesn’t recognize it and wants to exclude it. Or, worse, the USDA agent could accidentally miss a prohibited species and allow it through. Make sure you read and can understand the guidelines. If you have any doubt, you can call the Hawaiian USDA office, which I did, and get connected to someone who can offer guidance.

I went through the checkpoint at the Kona airport on the Big Island with 27 types of plants and cuttings. The agent only blocked one item from getting through—a bag of Crinum asiatica seeds that were still very green and fleshy. She picked out a couple other seeds here and there that looked damaged, letting me keep the rest. She took a close look at some agave bubils to make sure they weren’t some type of cactus, and that was that. After inspection, the plants went into a cooler that was tagged with a USDA sticker, and arrived in Denver for me to process and propagate.

Additional safeguards

After getting my cuttings home, I’m still not going to take any chances that some unusual organism slips through. They are being nursed and propagated indoors, in most cases under a plastic humidity dome. That way I’ll be able to observe them for some time as they get growing. You can read a bit about general plant propagation techniques here. But in my next post, I’ll write more about bringing these particular little stems and seeds to life.