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Food For Thought: Orchard and Pasture Weeds
Making friends with the neighborhood bullies
I'll tell you a secret: find ways to use the power of "invasive" plants and your life will get easier. This little article is intended just to get the conversation going.
Cane grass (Elephant grass, Pennisetum purpureum): We see the stuff all around, and it mostly brings to mind the thought of abandoned, underused land. In Puna, the papaya fields lie fallow in cycles of several years, and cane grass is usually the primary invader. This plant makes a thick, impenetrable barrier up to twelve feet tall. Cane grass grows readily from nodes, and seasonally disperses wind-blown seed. I have looked at cane grass as an annoying invasive plant pest...until I didn't.
I am proud to say that I am one of only two people I know who have planted cane grass. You see, I had goats, and I started to notice that they liked it. I would drag them bundles of the stuff. Then, when they took the leaves off I would plant the bare cane in a fallow pasture. As time went on, the cane grass began to take over parts of the pasture. The goats couldn't keep up with it, until one year we had an extended drought. Nothing else was growing. Just about when the six month drought was over, the goats had about finished the stored up food in the form of cane grass. This "bank" of food held them over through tough times.
I have a friend named Clive who has acres of cane grass which he cherishes for only one purpose: he mows it with his tractor, then hauls it to feed his taro, tumeric, ginger, papayas, pineapples, etc. So, for animals or plants, cane grass is one of the very best biomass producers. When you are done with it, then knock it or cut it flat and cover it with sheets of weed mat fabric. Three months of total shade will kill the stuff, leaving you with a rich, plantable layer of mulch. Incidentally, cane grass is very light sensitive, so allow fast-growing trees to grow and they will shade it out and make it more wimpy.
Maile pilau (Stink Vine, Paederia foetida): My warm feeling toward this vine is because all ruminants love it. I used to coax my herd of sheep into a new paddock with a bowl of grain. To my surprise (and glee), the sheep frequently ignored my offering in favor of eating the stink maile on the fresh pasture. At times I encourage this weed to grow onto my cane grass so I can watch them duke it out.
The soft weed trees: Albizia, Melochia, Cecropia, Gunpowder tree
These four are super fast growing, soft wood, and tolerant of poor soils. The first one (Albizia) is nitrogen fixing. The other three are carbon fixing, which translates into soil building. Let's be thankful for the fertility that these wonders create. I encourage these trees to grow around my fruit trees and banana plants. I periodically cut them back when they are a few inches thick, and use them as a source of mulch for my orchards. I just make one or two swipes with my machete, and leave them lying where they fall. As they become humus, the roots of my orchard plants will find it. When you plan out your orchards, leave some space for this sort of biomass production in between your trees.
Albizia (Albizia zygia; and Siris tree, Albizia lebbeck): because it is nitrogen fixing, it makes high protein animal feed. A goat favorite. They browse the leaves and eat the seasonal bean pods. It also makes useable wood.
Melochia (Melochia umbellate): the inner bark makes surprisingly durable fiber for cordage or weaving.
Cecropia (Guarumo, Trumpet tree, Cecropia obtusifolia): It's my favorite for chopping because it is very soft wood. The fruits have a pleasant taste like fig newton. (it is remotely related to fig) Leaves are medicinal.
Gunpowder tree (Trema orientalis): old, full-grown trees make millable wood. However, I know of three farmers (including myself) who have had goats die from browsing this tree.
The harder weed trees: Guava, Ironwood, Haole koa
These trees grow about as fast as the softer weed trees, but they are less fun to cut for biomass, since their wood is harder. I would use these plants for colonizing poor soil areas, or for goat food.
Guava (Strawberry guava, waiawe ulaula, Psidium cattleianum): makes good poles for farm structures. I made a frame for our farm sink from green strawberry guava, and after ten years of spills and daily wettiing it is still solid. When we fed our goats baking soda, they increased the amount of guava fodder they ate. We have used stands of guava as a trellis for Lilikoi and Chayote vines.
Ironwood (Casuarina equisetifolia & C. cunninghamiana): is nitrogen fixing and a pioneer tree, which means it will grow where nothing else will. It's nowhere near as resistant to decay as guava, for instance, but I've built structures with a few thousand linear feet of the poles, and after ten years the dry stuff is mostly holding up fine. We planted ironwood trees along the edge of a deep crevice to discourage undergrowth and increase visibility.
Haole koa (Koa haole, White lead tree, Leucaena leucocephala): will grow anywhere, it's nitrogen fixing, and a goat favorite. I prefer it in pastures because it stays relatively short.
Remember, all these plants are considered rampant weeds. People will laugh at you for growing them, or even tolerating them. Make friends with these ubiquitous plants, but honor their power.
Scott Middlekauf lives with his wife Karin Payne on their 22 acre sustainable farmstead in Kapoho. You can read their fascinating blog at EveningRainFarm.com.
Editor's note: Please do not introduce invasive plants to an area where they are not already naturalized, where their presence could become a nuisance to others, or where they could escape into native habitat.