Environmental weeds: Merrily berrying!

“A berrying we will go; a burying we will go....”   Well, not the second kind of burying, actually.

It’s remarkably easy and quick to cut the berries off the woody environmental weeds that are flourishing in our garden and in local patches of bushland.

On Sunday, in a 2-hour ‘weeding bee’ on Mt Rogers*, 8 people snipped off enough berries on twigs to fill a box trailer (with cage), packed tight, to about 1 metre deep. Just using secateurs or loppers we completely harvested the red and purple berries on bushes of Cotoneaster (Cotoneaster species), Hawthorn (Crataegus monogyna), Briar rose (Rosa rubiginosa), and Privet (Ligustrum species). These woody shrubs, viciously prickly in the case of Hawthorn and Rose, have been taking over the hillside where we were working, shading out and crowding native shrubs and grasses.

There were signs that kangaroos have been roosting under one of the Privet/Hawthorn tangles, and again elsewhere under a dense Cotoneaster bush. But they can go on doing that — we only cut off the berries on Sunday; the main structure of the bushes is still there, though more open to let light through.

Autumn is the time when the berries are present and obvious, and easy to remove before the birds eat and spread them out everywhere to germinate in spring. Once spring comes, we will return to these bushes, cut the stems near the ground and dab them immediately (within 5 seconds) with weedicide. That is the best way to kill the roots, it seems, to get rid of the plants altogether.

After we’d all had a break for a cuppa and a welcome muffin, the trailer’s owner set off for the green-waste tip, taking the yield of our 16 person-hours of work.

Weeding bees once a month are a rewarding way to spend a couple of hours outdoors (especially if it’s not raining) giving oneself a glowing sense of goodness!!

In fact, I personally think that community working groups are an excellent way to tackle weed control, for species that don’t need to be sprayed in large areas (such as grasses). The more community members who join in, the more that can be done, of course. If the job were to be left entirely to government employees, it would be very costly to pay enough of them to control the woody weeds, because though easy work it’s labour-intensive.

*Mt Rogers, in the north-west part of Australian Capital Territory, is a mound 704 m above sea level (at the top), derived from volcanic activity 425 million years ago (or thereabouts). It is crowned by native bushland, and entirely ringed by suburban gardens, .and it offers fabulous views of New South Wales and Canberra. 

(Vehicles were only allowed onto this track for the working bee.)

Environmental weeds: Surely not in the garden?!

It’s autumn, and the bright red berries on the big evergreen Cotoneaster bushes in our garden are attracting the Crimson Rosellas and other birds, and adding highlights to the fencelines where green is the only other colour. The berries are beautiful! And a problem too!

Say the birds eat the berries and then pooh them out elsewhere, tomorrow or the next day (how long do birds keep food in their guts?), perhaps in native woodland or grassland. Then the seeds sprout and start to take over that patch. Plants that behave like that nowadays get listed as ‘environmental weeds’ — garden escapees, too active, too attractive (e.g. to birds), and altogether too competitive!

So we really need to control our garden Cotoneasters, or their berries (what a huge job!), for the good of the environment. And actually, having thought about it, I’ve just seen how, over time, we can rid ourselves of these plants without losing the benefits they give us now.

Hey, it’s not just our garden! We’re not the only people who have Cotoneaster or Privet, Ivy, Bamboo, Hawthorn, etc. Some gardens have Periwinkle and Honeysuckle and Broom and Gazanias as well! And that’s not the whole list by any means. Environmental weeds are in gardens in every state and territory of Australia. Until relatively recently, these competitors were the sorts of species you normally planted when you bought a house and land in a suburb or country town. The species that are ‘environmental weeds’ now weren’t seen as environmental weeds then. They were welcomed as being fast-growing, colourful and attractive to birds! Just the characteristics they’re now reviled for.

This is a challenge for environmental weed controllers. These plants are widespread in cultivation, and many gardeners want them for the roles they play in the garden. ‘And why not?’, one could ask. It’s only when they escape that they become a problem.

But what a problem! Two really invasive examples are Lantana, and Water Hyacinth. Fireweed, currently on the rampage, may also have ‘jumped the fence’ from a garden originally. And there are many many others.

Okay, back to our garden. We want privacy, beautiful and fragrant flowers, visiting birds, soil held in place by strong groundcovers, and so on. I reckon we must attack our own environmental weed species in stages, replacing one or two plants at a time with fast-growing alternatives such as wattles or bottlebrush! That strategy should spread both the cost and the need to find alternative screening options along the fencelines. Other plants will provide birds with food and cover till the alternatives are big. After all, ours is not the only garden in the area with berries!

You could ask ‘Why bother to control your environmental weed species if other people nearby don’t do the same thing?’. Well, others nearby probably are doing the same thing. The word seems to be spreading. Nurseries don’t sell these species any more, and the Nursery & Garden Industry of Australia has produced ‘Grow Me Instead’ booklets for every jurisdiction. Many people have visited the demonstration garden, at Floriade in Canberra each year, where local environmental weeds (in pots) are matched to replacement alternative species. And many people dump loads of environmental weeds during Canberra’s twice-yearly Weed-Swap weekends (March and October). (They are given a free native plant in exchange for their weeds!)

We’d better get to work on our attack Stage 1, while the soil’s still warm enough to plant replacements. And then there may be some time to get out to join the local Landcare groups’ weed working-bees that are helping clear environmental weeds from the native woodlands and grasslands. But that’s another story...

AM

Related links:

National ‘Grow Me Instead’ program: http://www.ngia.com.au/Category?Action=View&Category_id=151&Highlight=weeds (Nursery & Garden Industry of Australia)

Cotoneaster: http://www.weedsbluemountains.org.au/cotoneaster.asp

Fireweed: http://www.dpi.nsw.gov.au/agriculture/pests-weeds/weeds/profiles/fireweed#

Lantana: http://www.weeds.gov.au/publications/guidelines/wons/pubs/l-camara.pdf

Water hyacinth: http://www.dpi.nsw.gov.au/agriculture/pests-weeds/weeds/profiles/water-hyacinth#

Caption to photo: One of our Cotoneaster shrubs right now. These leaves are about 2 cm long. Other Cotoneasters in our garden have leaves 4-5 cm long, and their berries hang in bunches.