Linda and Roger's Bunhybee Grasslands
Weed Control Plan
This is a page within Roger and Linda's
Bunhybee Grasslands Web-Site.
Bunhybee Grasslands is a 49 hectare / 120 acre conservation
property 35km south of Braidwood, in southern N.S.W.
You can follow through the internal links, or you may find it
easier to use the Site-Map.
This is a subsidiary page to the Action Plan. It contains
our plans on how to tackle each category of weed on the property. It draws on
various sources, including our own experience.
Some guidance is in the Management Plan (2.7 pp. 26-27, App. B p. 41, App.
F p. 52 – a DPI brochure, App G p. 53). We have also drawn on a variety
of Weed Management Resources.
The weeds that have been identified on the property are catalogued here:
Here is a map of the weed infestations when we took possession
at the end of 2008.
The weeds for which we have control plans in place are as follows.
They are in roughly descending order of concern:
Notes on other weed species are here:
Progress against this Plan is reported in the separate page on Weed
Control Implementation.
For photos, go to the Bega
Valley Plant Index, and key Nassella trichotoma into their search-engine.
1. Identification
- Distinguishing S.T. from native tussocks (Poa spp. esp. young sieberiana
and Stipa spp. esp. setacea) can be very difficult at first. After
paying attention to grass for a couple of annual cycles, most people end up
pretty confident once they get up close
- Many sources and individuals suggest many different identification techniques,
which are inconsistent, season-specific, possibly area-specific, and in many
cases unreliable. In particular, we have not found it very heplful to roll
the stem between thumb and forefinger (because it's a round stem, not oval
or rectangular), nor to rub the thumb and forefinger down the stem towards
the ground to detect the roughness / serration.
- A grazier may be happy to eliminate low-yielding native tussock at the same
time as S.T. But a conservationist has different priorities. Occasional elimination
of a native tussock under suspicion of being S.T. is not a big issue, but
if the mistake can be made once, it can be made many times
- Our recognition technique, all year except mid-summer:
A tight, relatively erect clump, with relatively bright green strands interspersed
with straw-coloured strands, relatively tight and relatively dark compared
with other tussock species
Drawing a single stem up out of the clump is relatively easy compared with
the other species
- Our recognition technique in early summer (roughly, early-to-mid
November)
Dark seed-heads on diaphanous glumes, whereas Poa spp. seeds are
less readily seen, and Stipa spp. seeds and seed-heads are lighter
in colour
- Our recognition technique in mid-summer (roughly, late
November to mid-December)
This is the easiest way to differentiate them, but
it's risky, because of the escape of seed.
Mauve/purple seed-heads on long glumes, bending under the weight of the seed
to produce a 'mauve peacock's tail'
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Four foreground,
six middle-ground |
Serrated Tussocks
appear dark and tight |
Six clearly visible here |
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A patch of nearby Stipa |
Click on any image ... |
... to see a larger version |
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The plumes of the nearby Stipa |
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Left, Right in each photo ... |
... the Serrated Tussock, and the Stipa |
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The darker image of Serrated Tussock |
4 Serrated Tussock,
diagonally up the right |
2. Attack Timing
To avoid seed-dispersal, the preferred times are:
- any time of year, if you're confident in your identification
- early summer, before the seeds are viable (roughly, early-to-mid
November)
You may have to attack in mid-summer (in the Southern Tablelands, variously
late November to early January), in order to ensure reliable identification
(or because that's the first time you notice it!).
3. Attack Method
Our treatment in early summer (roughly, early-to-mid November)
The seed is forming, enabling confident identification, with limited risk of
dispersion of viable seed
- use a mattock to get under the clump from the outside
- lever and draw out the multiple intertwined plants
- if you fear the seed may be viable, bag the heads and seal-and-leave, or
remove-and-incinerate
- knock off the larger lumps of dirt
- pat down the dirt
Our treatment in mid-summer (roughly, late November to mid-December)
Seed-heads are already well-developed, for easy recognition, but with high risk
of seed-dispersion
- do not dig out while the glumes are on it, because that will spread
the seed
- clip the top of the glumes (roughly 9" to a foot), place carefully
in a bag, then seal-and-leave, or remove-and-incinerate
- after that possibly dig the clumps out; but it's a much higher priority
to get rid of the seeds than it is to remove the plants (which can be done
any time in the next 10 months)
Our treatment at other times of year
If we're confident in our identification, we use the same method as
in early summer, above.
If not, we mark it down for re-inspection in early summer.
Alternative treatment is:
- Use a narrowly-targetted spray on the body of the tussock
- Use a spray comprising glyphosate (e.g. Roundup) 3ml per litre, TaskForce
3ml, surfactant 2ml, and some dye (so you see which clumps have been sprayed)
- [But, whereas Glyphosate breaks down, TaskForce doesn't, and is very nasty]
- Preferably attack it early enough in the growing season that knock-down
will occur before the seeds mature. (But, as indicated above, difficulties
in identification make that difficult to achieve)
- If attacking it sufficiently late that the seeds will or may mature, carefully
remove the heads first (clip the top 9", place carefully in a bag, then
seal-and-leave, or remove-and-incinerate)
- Use a narrowly-targetted spray on the body of the tussock. (Maybe 20ml of
one of the mixes below per full-grown tussock? No sources appear to provide
such basic information!)
4. Herbicide Choices include:
- glyphosate (e.g. Roundup). Knock-down is slow, so treatment
appears to have to be at least 6 weeks before seeding, to prevent the seeds
becoming viable. Surfactant is recommended (i.e. a wetting
agent that encourages absorption by the plant by lowering the surface tension,
e.g. a little washing-up liquid). Dye is recommended (so
that it's apparent which tussocks you've already sprayed. Dyes can be purchased,
or a natural substance can be used, such as beetroot juice)
- fluproponate (e.g. Task Force). Knock-down is faster, so
it's more likely to help later in summer. Surfactant is unnecessary. Dye
is recommended
Herbicide Mixes of various kinds are recommended by various
sources. They include:
- glyphosate – 10ml per litre (ml/l)
- glyphosate – 5-8gm per litre (c. 5-8 ml/l?) – WA(2003) below
- glyphosate – 10ml/l plus fluproponate – 2ml/l
- glyphosate 3ml/l, fluproponate 3ml/l, surfactant 2ml/l – Helen Thompson,
Clth Dept of Environment
5. Sources
Recognition is easy. There are multiple
native Rubus species, most commonly Native Raspberry (R. parvifolius).
But they have smaller leaves and less prominent fruit, and we have found none
on the property.
Blackberry is an eternal weed, because of continual re-infestation from nearby
properties mainly transmitted by bird-poo. Blackberry grows very rapidly, trails
across to establish new roots 1-3 metres away, and re-grows vigorously from
existing roots. Because large bushes are a great deal of hard work, early action
on new bushes is vital.
On large properties, and with large infestations, spraying and raking may be
necessary. But we had the advantage of relatively small areas of infestation
(1 x 20 sq.m., a dozen 2-5 sq.m., and a couple of score of 1 sq.m. bushes),
and have adopted a different approach on Bunhybee. See the Blackberry
Control Manual.
We use a variant of cut-and-paint, using glyphosate, which is described immediately
below. (See the generic description of Cut-and-Paint).
It is labour-intensive (indicative 6-10 sq.m. in a 2-person 5hr-day). But it
is very effective, and can even achieve one-round knock-down.
Timing:
- Easily the best time to attack is late summer (late Feb to early
April)
This is because the plant is withdrawing its sap from its extremities,
and hence draws the poison down to the roots
- There are two lesser reasons for an attack in late spring / early
summer (Sep-Oct):
- to get to it before it fruits and the birds get to the berries
- to achieve a pre-trim of canes and make it easier to attack in late
summer
- There's no point using poison-based attacks in autumn, winter or
early spring
(although a manual or mechanical attack may make sense at those times)
The Preparatory Attack:
- This can be done immediately before the attack proper. It 's best not
to do it more than a few weeks beforehand, because otherwise the re-growth
can negate the effort
- Cut canes into carriable lengths (c. 2 feet), and put them into carriable
piles
- Cut canes in such a way that every plant is visibly exposed and physically
accessible, i.e. leaving perhaps 1-3 feet of cane that can be later poisoned.
(A bush 6 feet long and 4 feet wide might comprise 40 or 50 separately rooted
plants)
- Stack the cut canes on rock-shelves, because otherwise they'll re-strike
(second-best is to stack in large piles)
The Attack Proper:
- Cut-and-paint with glyphosate, max. 3-5 seconds from cut to paint
- We've done it with one or two people, but one usually works better for us
- All branches need to be cut-and-painted, and there may be scores
in one plant
- Where young leaves are still present low on the stem, paint them too
This is a biennial, which grows a rosette in its first year, and a stem in
its second. It can produce large numbers of buds, each of which contains large
numbers of seeds (c. 50?), which float clear of the dying flower and mostly
fall close by. The species is cunning in that it typically has one early flower,
followed by a succession over the summer and autumn. Green buds and the bowls
beneath the purple flowers contain seeds; but old, open heads have probably
already released them. The plant appears to reliably expire after its one
season of fruiting:
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Mature, unopened heads |
... showing viable seed ... |
... still inside |
Old heads, after releasing seed |
We've come across the theory that thistles can, in some circumstances,
act as valuable colonisers and soil-improvers, and may be transitory (although
for some years). None of the areas where we've found them need that; so in all
cases we've treated them as weeds needing removal.
We've mainly worked out the following treatment methods for
ourselves, but an
excellent US Forest Service source that we've found since has confirmed
most of our thinking.
Rule 1 is that good, thick gloves are essential,
preferably gauntlets, i.e. with lower-arm protection.
If the plant is in its second year and has a stem
There may already be viable seed even at the time flowering begins.
The plant needs to be removed, because, until as late as the end of summer,
the species is highly resilient, and is capable of forming many further buds,
even on a chopped stem.
- Clip off all flowers and green heads, place them carefully in a bag, then
seal-and-leave (best done in a black bag, to maximise the heat), or remove-and-incinerate.
- Destroy the remaining plant. Alternatives include (best first):
- get a grip low on the stem, and ease the whole root out of the ground,
shake the dirt off, and leave the root exposed. But that approach needs
moist soil, strong back (especially when done in quantity), and of course
good gloves
- use a hand-mattock to chop out as much of the root as practicable, minimising
the ground disturbance, and leaving the root exposed and clear of the
ground
- cut the foliage off the root, then cut below ground to separate the
root from the remainder of the plant, or stab down into the root to expose
it to air and dry it out
If the plant is in its first year and still just a rosette
Alternatives include (best first):
- get a grip around the rosette, and ease the whole root out of the ground,
shake the dirt off, and leave the root exposed. But that approach needs moist
soil, strong back (especially when done in quantity), and of course good gloves
- use a hand-mattock to chop out as much of the root as practicable, minimising
the ground disturbance, and leaving the root exposed and clear of the ground
- cut the foliage off the root, then cut below ground to separate the root
from the remainder of the plant, or stab down into the root to expose it to
air and dry it out
If the plant is aged and all heads are open
There might be seed left, but mostly it will have flown. Pulling the stalk
out is more of an aesthetic matter than a weed management measure; but we tend
to pull them
Other Thistles:
At this stage, we've treated the few that we've found the same as Cirsium
vulgare. See above
Yorkshire Fog (Holcus lanatus)
- This is easiest to distinguish in spring / early summer (Oct-Nov) when it's
fresh and soft, with long (pinkish? bluish?) plumes, and stands higher than
other grasses at that time of year. The colour fades to straw in Dec.
- Hopefully it will be feasible to tackle it then, well before it seeds
- A challenge is that it grows in moist areas and mixed / intertwined with
native species
- Possible approaches are:
- uprooting
- centre-spraying
- Zelma's Method (glove-applied glyphosate)
Phalaris (Phalaris aquatica)
We're trying two alternative approaches:
- spraying. Early indications are that this can be reasonably
effective, but the collateral damage on the native grasses that are intertwined
with it is substantial
- chopping out. The first attempt was in winter 2011 (late
July). The advantages of doing it in winter are that the native grasses are
relatively flat and dull at that stage, and the phalaris stands out as striped
bright-green and very light brown. The soil was moist, and with some practice
it became quite quick to strike with a hand-held mattock or full mattock (one
to four strikes per clump), getting sufficiently deep to turn the complete
plant upside down. We did a quick check to see if there were any natives caught
up in the clump that could be rescued, and to break off any excess soil back
into the hole. We then left most of the clumps upside-down back in the holes
they came from, or in a pile, in either case with the roots exposed
- We've treated mostly by Cut-and-Paint, using glyphosate-only,
cutting them down close to ground-level (requiring multiple cuts for anything
other than young plants)
- If we don't have glyphosate to hand, but do have secateurs, we cut low,
and break the remaining stem in the ground
- The cuttings can be left to compost, or to bake on a rock
- If it's late summer and there are viable rose-hips, we clip them off, place
them in a bag, and then seal-and-leave, or remove-and-incinerate
See the photos at the Bega
Valley Plant Index
- Generally, we ease the plant and roots out, remove the soil from the roots,
and leave the plant lying on the ground to compost, roots exposed. (In most
places at Bunhybee, the vegetation is thick enough to protect the disturbed
ground, and the dirt is soft enough)
- If pulling the plant out appears likely to leave disturbed ground open to
invite other weeds in, it can be cut down to ground-level and the remaining
stem broken in the ground, leaving it to dry out and the remnants to compost
Other Grasses
Apart from Serrated Tussock, we're only progressively getting to grips with
the other introduced grasses. Initially, it was challenging to distinguish some
of them from the many native grasses. And because introduced grasses are commonly
inter-twined with native grasses, it's proving challenging to devise appropriate
control techniques. The other grasses for which we are developing plans are:
- Paspalum (Paspalum dilatatum).
This is inter-twined with poas and stipas, in particular on the main dam wall
and nearby, below the track just above the small dam, and at the bottom of
the southern watercourse (SW corner)
- Fescue (Vulpia sp.)
These are in a variety of areas, and are easily mistaken for Microlaena until
it's mature (when it's considerably taller)
- Sweet Vernal Grass (Anthoxanthum odoratum)
We think this is in moist areas – but we're still working on identification
of this one
Techniques that we're experimenting with are:
- 'Zelma's method'
We wear cotton gloves (over plastic inners for protection), dipped
in glyphosate mix, and stroke the herbicide onto the plants. We need to understand
the means whereby glyphosate harms such grasses, and whether that kind of
treatment gets the poison to where it needs to be
- Narrow-spraying
This needs to be into the heart of the plant, trying to limit the
collateral damage to native plants close by and entangled with the target
plant
- Hand-pulling
This can be done with species that are clumped rather than matted (which applies
to most of the introduced grasses on the property).
It's a bit tedious and back-breaking, and hence is best done for only an hour
or two.
Initial trials suggest that it can be very effective, provided that identification
is confident, it's done without spreading viable new seed, and the roots are
left exposed.
It can be done with hands alone, but usually a hand-mattock or mattock is
needed, with 3-5 strikes around the base of the plant, striking deeply enough
to get under the roots rather than through them.
It may be necessary to disentangle native species before striking, and to
rescue native species and shake excess soil off the roots and back into the
hole, before upturning the clump. We're experimenting with (a) upturning the
clump in the hole, and (b) tossing them into a pile and leaving the space
to look after itself (knowing that there will be some introduced species among
the pioneers, but trusting the natives to win out a lot of the time)
Other Flowering Plants
At this stage, we have no plans in relation to the other flowering species.
One reason is that the native species are strong, and most other weeds are either
seen only occasionally or present few problems. For example, flatweeds are early
colonisers of broken ground, but appear to be swamped by natives as time goes
by. We've not concerned ourselves with Dandelion (Taraxacum officinale),
which is everywhere and appears to be fairly harmless anyway; nor with Scarlet
Pimpernel (Anagallis arvensis).
We have some concerns about:
- Sorrel
(Rumex acetosella and/or Acetosella vulgaris?).
See the photos at the Bega
Valley Plant Index. If we need to address it, then I imagine that we'll
treat it as for Fleabane
- Hawkweed (Tolpis umbellata/barbata), which appears
as if it may be spreading quickly. If so, it may need hand-pulling or even
digging (because its has very limited foliage to spray, and hence the collateral
damage from spraying would be high). On the other hand, the
Southern Tablelands and South Coast Noxious Plants Committee says "The
small weed Tolpis umbellata or T. barbata is sometimes referred to as yellow
hawkweed, but it is not one of the Hieracium genus and is not listed as noxious
in NSW. It is generally only a minor weed of waste ground and roadsides".
Nonetheless, it would be nice to work out how to tackle it
This is a page within the Bunhybee Grasslands Web-Site, home-page
here, and site-map here
Contact: Linda or Roger
Created: 14 December 2008; Last Amended: 23 January 2012
