Zoysia Seed To Develop a New Sports Oval - Part 2 - Seedlings at Four Weeks from Sowing and Weed Management

While early seedling growth was very good, the dreaded weeds then started to appear!

While herbicides for use on seeded zoysia have been a bit tricky in being able to choose one that had minimum collateral damage to the small zoysia seedling yet was efficacious in removing weedy plants, we decided to use quinclorac [trade name Drive], which will deal with some weedy annual grasses and many broadleaved and leguminous weeds, selectively, without damaging the zoysia seedlings.

Timing is still important...............very important.  It is important to apply Drive in the period of 14 - 28 days after emergence, and in our situation we had major emergence about 8 - 9 days after sowing and we sprayed 25 days after sowing, about 16-17 days after emergence.

Results have been good, with strong control of leguminous and broadleaved weeds, and some weedy seedling grasses.  More work will be needed over the next four weeks to deal with some of the weeds remaining which includes some broadleaved weeds as well as sedges and grasses.

About 4 weeks after sowing we also applied additional fertiliser [ Yara Hydrocomplex ] at a rate equivalent to about 30kg/ha of N.  Included was another approx 10 kg/ha P and 35kg/ha of K and more trace elements and sulfur.

With other species, more fertiliser is used eg couch, but trials have shown there is little additional growth benefit by applying more at this stage to seed sown zoysia, either Zenith or Compadre.  We expect to apply more fertiliser in about another four weeks.

Seedlings are growing well, weeds are mostly dying and the oval is developing steadily.  Yes, there is some uneven seedling distribution, but we did have a very high intensity rainfall event soon after sowing which resulted in washouts, which would have been much worse without the hydroseeding and use of mulch.

Over the past four weeks an early morning irrigation was applied almost every day, along with two very short daytime irrigation periods to boost dampness near the soil surface.  Some might have thought this irrelevant, as there has been quite a reasonable amount of rain - almost daily [ a few days break here and there] but it is essential to keep the surface damp in this initial period, especially as we often had hot sunny days.  Irrigation is now being reduced to three or four times a week, even though we are still receiving an occasional amount of  effective rain. Irrigation will be likely further reduced in coming days, if rain continues.

The next major exercise will be to start light mowing to enhance lateral growth of zoysia and help control any remnant weeds, and to continue with several other herbicide options for ongoing weed management.

weeds dying amid zoysia seedlings after selective herbicide application

close up of zoysia seedlings

overview of oval development at 29 days from sowing- some unevenness, but most areas with high seedling density

close up of dying weeds among zoysia seedlings  - note leaf twisting and colouration

overview of weeds dying at one corner with plenty of zoysia seedlings developing

All photos taken 29 days from sowing.

Dioxin Found in Imported Phenoxy Herbicides in Australia

There has been a monster fuss over dioxin in the phenoxy herbicides used in the 1970s.  Agent Orange, helicopters, defoliation.....Vietnam era one says.........the manufacturers do it better now.

The good ones do.............but with a race to the lowest cost product for the ultra competition which drives the cost issue in agriculture and horticulture in Australia..............guess what?  Imported product has suddenly appeared on the scene with plenty of dioxin present as a by product of the production of technical grade 2,4-D and 2,4,5 -T.  Same  quality control issue as the 1970s, one would suspect.

Phenoxy herbicides are not banned and many do a great job at low rates, and modest cost.  Combination products are widely used - eg 2,4-D and MCPA or dicamba, and often in horticulture and even home garden use as turf herbicides.  2,4-D was probably the first real herbicide and has been used since the 1950s.

But the costs have fallen and there are many manufacturers in China, and some it now seems are really cutting corners.

Yes, Australia has probably not done enough monitoring of ongoing imported products either. 

As is often the case, initial supply is fine - meets specifications etc.  As volume goes up.......sadly, quality plummets!  Or a different lower cost producer replaces the decent producer who is meeting quality requirements and the exporter [ often not the producer] says little.......but quality is going down, but not enough to indicate the product is not doing its job. 

It is the by product that is the problem - dioxin.

Herbicide spraying - Vietnam war era.

It is deadly stuff.............look it up eg wikipedia, plenty of detailed reports on line.  It is VERY NASTY!

It is unclear how widespread the problem is in Australia, but some believe that it is not major, restricted to some importers and formulators using lower cost product to drive their sales into the market.  It might take some time to sort out, but as a guide.........BEWARE if using phenoxy herbicides.  You should be now anyway.

Everyone seems to have thought the dioxin issue was dead and buried.........and with quality technical product from quality manufacturers it broadly had not been an issue for many years.  However, it is back.

It is interesting to also speculate how much poor technical product also went into other Asian countries - Malaysia, Vietnam, Laos, Burma, Cambodia etc where cost is probably an even bigger concern.  They are unlikely to have respected regulators to get on top of this issue.

Is it any wonder many do not trust Chinese product?  Whether agricultural chemical or baby formula, seems immaterial - they are suspect, and one wonders why Chinese want our rural products???

See - http://www.abc.net.au/news/2013-07-23/industry-supports-regulator/4838078

and http://www.abc.net.au/radionational/programs/bushtelegraph/dioxin-follow/4837862


UPDATE - also see this article from later in the week after the blog written.

http://www.queenslandcountrylife.com.au/news/agriculture/cropping/general-news/dioxins-slip-through-system/2665361.aspx?page=2

Overcoming Herbicide Resistant Weeds

This issue is an important one in Australian agriculture especially in areas with annual ryegrass as a weed.  While there are also some areas with herbicide resistance in summer grass and some other weedy species, it is the annual ryegrass issue now more regularly occurring in much of the temperate grain production areas.

Worryingly, a recent survey has highlighted the poor knowledge that farmers have about the issue in general.  Alternately though, it seems consultants and advisors are quite knowledgeable about management of problems.  But it is imperative that the issue is addressed through management on farm.  This work was done by Monsanto on glyphosate and reported here - http://www.queenslandcountrylife.com.au/news/agriculture/cropping/general-news/glypho-knowledge-gap/2660339.aspx?storypage=0

Loss of major herbicides would be a disaster, at least in the short term.

A recent innovation in WA by one farmer has been work on developing an amended chaff collection system, which allows in paddock burning of the collected weed seeds. More here -
 http://www.queenslandcountrylife.com.au/news/agriculture/cropping/general-news/chaff-cart-hits-weeds/2663626.aspx?utm_source=newsletter&utm_medium=email&utm_campaign=newsletter

and a video here - http://www.grdc.com.au/Media-Centre/Over-the-Fence/Over-The-Fence-Videos/Over-the-Fence-Western-Region/xZkRlAf-KCk

But this farmer also uses standard recommended practices of rotating herbicides, crops and managing the weedy species to prevent seeding [ through hay production prior to seeding]. 

There is also a new seed destructor system now appearing in some areas, which destroys the seeds after harvest.

Harrington Seed Destructor - tow behind model
 

http://www.grdc.com.au/Media-Centre/Ground-Cover/Ground-Cover-Issue-104-May-June-2013/Harrington-seed-destructor-development-continues and there are a few more articles on this system on the GRDC web site - www.grdc.com.au and search.

Managing herbicide resistance is not an easy task but a necessary one, and using low doses inadequate to kill all the target weeds is not a sensible option, and false economy.

What is at stake is the continued use and development of minimum tillage, seen as a great advance in cropping over the past 40 years, and certainly contributing to lowered costs and greater efficiencies in grain production systems, generally world wide, not just Australia.

Fake Agrochemicals - Farmers BEWARE

It had to happen........the rural and related agrochemical and fertiliser industries are worth many millions of dollars and both agrochemical and fertiliser sales annually are also worth millions of dollars, even in a relatively smallish market such as Australia.

A recent scam involved sales of dirt.......yes common soil.......as a marketed and manufactured fertiliser from an overseas source, with the material actually making it to a rural location before detection. That also was a major biosecurity concern, as well as a straight out scam.

With input costs a major factor in producing crops, shaving these by a few dollars can be important. But the new scam is to produce suspect agrochemicals for sale. They do not perform as expected and often on investigation, formulations are just plainly wrong, or they even are made using dodgy liquid ingredients including tainted and dangerous wastewaters, or may not even contain the active technical ingredient, or contain by product chemicals that could damage crops.

Yes, there are successful low cost reputable formulators, capable of offering suitable agrochemicals at discounted prices, and supplying to Australia. But it is very necessary to be sure about who you are dealing with and their reputation, both technically and financially.

Needless to say, China seems to be a source, but some eastern European operators are also involved.

The old maxim applies .......if it seems to good to be true, it probably is too good to be true!!

This is expanded further in a recent on line article:
http://qcl.farmonline.com.au/news/nationalrural/grains-and-cropping/general/fake-chemicals-pose-risk/2299664.aspx?storypage=0

It should also be remembered that any agricultural chemical used in Australia should have been assessed and given the okay by the relevant Australian authorising agency, the APVMA.

If in doubt have a look at their web site, www.apvma.gov.au and this statement is off the web site -
'Before an agricultural or veterinary chemical product can be legally imported, supplied, sold, used, promoted or advertised in Australia, the APVMA must register it. Part of the APVMA's role and responsibility is to monitor and enforce compliance of agricultural and veterinary chemical products in the market place."

SO BE AWARE.

Could Roundup Ready GM Crops Induce Nutrient Deficiency?

The answer appears to be yes, but only due to the mode of action of the glyphosate. Longer term, overuse of glyphosate or continual regular use without other products use, may lead to mineral tie up in soils...........and nutrient deficiency. No doubt, this can be adjusted, with additional fertilisers.

But the real issue is, as Monsanto has proclaimd loud and strong for almost forever..............do not continually use glyphosate. There are issues of weed resistance, as well as potential nutritition issues. Trouble is.........some, possibly many, users are either not listening, or ignorant of the potential problems.

This does not necessarily imply using GM crops is bad. One needs to make informed choices, as already stated in a previous post.

Glyphosate is a very good and very useful chemical, probably the most successful product in this group - ever. Its ongoing efficacy requires users to use it properly.

The following article cover this issue in more depth.

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Glyphosate is to weed control what penicillin was to disease control in humans when it was first introduced. But as over-reliance on penicillin led (inevitably, as we now know) to resistance in disease organisms, so over-reliance on glyphosate has led not only to resistance in several weed species, but also to the gradual lessening of nutrient availability to plants.

Both trends have worrying implications for crop production worldwide.

Glyphosate resistance in weeds

Professor Stephen Powles, of the University of Western Australia, has identified glyphosate resistance in nearly a dozen species of weeds in North and South America (Powles 2008). Where only 14 years ago farmers began growing Roundup Ready crops, including maize, soybeans, cotton and Canola, which survive the direct application of glyphosate while everything else succumbs, the continued use of glyphosate alone – in direct contravention of Monsanto’s advice to rotate herbicides – has seen the emergence of herbicide-resistant weeds that mean crop failure. Powles attributes this sudden rise in weed resistance to the sole use of glyphosate on every crop by farmers eager to maximise their profits. This short-term gain comes at the cost of long-term viability.

Unlike in the USA, farmers in Canada regularly rotate their herbicides with their crops. The result is that glyphosate resistance is unknown in Canada (Holmes 2010). Powles emphasises that rotation is the only way to secure the continued viability of glyphosate.

Hidden nutrient deficiencies

A more insidious trend, although just as worrying, is the emergence of evidence that continued use of glyphosate can reduce the availability of nutrients in the soil, and that regular use on Roundup Ready crops can interfere with nutrient use by plants. Dr Don Huber, professor emeritus at Purdue University, USA, reports (Huber 2010b) that because glyphosate acts by chelating (tying up) certain metal ions, which are essential in plant enzymes, not only does it kill susceptible plants (by stopping the enzymes from working), but it also ties them up in soil.

He states that contrary to popular belief, glyphosate does not break down in soil (nevertheless, see the references in an earlier article that describe the breakdown of glyphosate by microorganisms), and that it can continue to tie up metal ions (some of which, such as Mn, Cu, Fe, Mg and Zn, are essential plant nutrients) in the soil, preventing plant uptake. (Certainly glyphosate bound to soil minerals is free to tie up metal ions.) He points to evidence of a long-term decline in crop growth in trials in Germany (Huber 2000a) as a result of glyphosate build-up in soil.

In addition to its effects in soil and susceptible weeds, glyphosate ties up metal ions within Roundup Ready plants as well. The resistance gene in Roundup Ready crops does not degrade the glyphosate in the plant; it simply bypasses its effects. So every time a Roundup Ready plant is sprayed with glyphosate, the plant takes up that glyphosate, which then adds to the store of locked-up nutrients in the plant. This effect explains the brief yellowing of resistant plants after an application.

The net result is a reduction in crop yields, both within the growing season and over several years. (Research cited by Wikipedia showed that crop yields were reduced by 6.7%.)

What you can do

If you suspect the emergence of resistant weeds, your best course of action is to switch herbicides for a year. Speak to your local district agronomist or district horticulturist for advice on suitable chemicals. Or use "double knock" techniques. There is additional material available from the web site of the GRDC - www.grdc.com.au

If you are worried about the locking up of nutrients, have your soil and plants tested. There are tests for the presence of glyphosate residues in both. If nutrient availability is low, we can advise you of how much of which nutrients to apply.

Further reading

Holmes R. 2010. Weed resistance could mean herbicide is futile. New Scientist 2760 (15 May): 12.
Huber DM. 2010a. What’s new in ag chemical and crop nutrient interactions. Fluid Journal 18(3).
Huber DM. 2010b. Ag chemical and crop nutrient interactions – current update. Botany and Plant Pathology, Purdue University, Indiana, USA.
Powles SB. 2008. Evolved glyphosate-resistant weeds around the world: lessons to be learnt. Pest Management Science 64(4): 360–365.
SESL. 2009. The Loam Ranger – Glyphosate.
Wikipedia: Roundup.

[latter information modified from other sources]

GM Crops Part of the System But NOT the Only Part

Using GM crops is a decision, just like any other farming decision. What to plant and how and when, what to use in a rotation.

Farmers are now advised to mix use of glyphosate and other products especially diquat / paraquat to ensure complete annual grass controls and minimise development of glyphosate resistance. Tillage might be part of the equation too.

GM crops are not a panacea..............with decisions about use considered in relation to many factors.

The recent article in an online version of the Queensland rural press covers these issues well. It is worth reading by both pro and anti GM camps to highlight decision making processes. Most are not so blind, that they cannot see................

http://sj.farmonline.com.au/news/state/grains-and-cropping/general/seeds-of-gm-discontent/1827512.aspx?storypage=0

Phytoremediate Explosives - Plant Grass - for a Quick Solution

Mounting evidence shows native grasses could destroy explosives pollution
The Kansas City Star

Missouri researchers are investigating whether native grasses can clean up pollution caused by explosives at hundreds of locations across the country.

Besides the obvious reason, TNT is not good for you.

But grass, it turns out, might be dynamite for the problem.

TNT contaminates hundreds of sites in the US and Australia, from military firing ranges to old production dumps to waterways, and poses a threat to the human nervous system and to the liver and kidneys. It’s suspected to cause cancer. It can cause allergic reactions and attack the immune system, and it may lead to birth defects.

Left alone in the soil, TNT breaks down into an even more toxic substance.

If the problem is left in the dirt, maybe that’s where the solution can grow.

Three Missouri researchers have hit on an idea that could potentially scrub away the TNT danger:
Simply plant the right kind of grass.

The notion started with mounting evidence that native grasses could render harmless a common weed killer. That herbicide, atrazine, is the second most common herbicide used in agriculture in the U.S. and has been a stubborn pollutant in the nation’s waterways. Mounting evidence has shown that certain native grasses, and the microbes that thrive around their roots, convert the toxic leftovers from atrazine into harmless carbon dioxide.

Robert Lerch, John Yang and Chung-Ho Lin began talking about how chemically similar atrazine is to the explosives TNT and RDX. “If it worked for atrazine, we thought it might work for these things,” said Lin, a research professor for the University of Missouri Center for Agroforestry.

Should their idea succeed, it would offer a greener, cheaper and possibly quicker way to clean up more than 530 sites across the USA contaminated by the explosives.

Trinitrotoluene, or TNT, and cyclotrimethylene trinitramine, also called RDX, began creeping into U.S. soil and waterways decades ago, before the manufacturers of explosives came under stricter regulation.

The problem isn’t small. Of the 538 locations identified by the US Department of Defense with RDX or TNT contamination, 20 are Superfund sites — classified by the federal government as the country’s most dangerous abandoned toxic waste sites. Congress rejected a Pentagon proposal in 2005 to exempt the military from regulations for pollution from munitions.

“It’s a serious problem, and it’s widespread,” said Andrew Wetzler of the Natural Resources Defense Council. To clear a field tainted by those explosives — typically to haul away the dirt for incineration — can run from $100,000 to $1 million an acre.

The researchers in Columbia have doped soil samples with explosives and planted two species of grass.

In essence, the explosives practically disappear.

It’s unclear whether it’s the grasses — Eastern gamagrass and switchgrass [Panicum virgatum] seem to work best — do the work themselves, whether it’s two forms of bacteria that thrive in soils around grass roots that do the trick, or if something happens in how they work together.

But in a closet-size room basking in fluorescent lights, a solution to explosives pollution looks to be taking root.

The scientists added RDX and TNT to cup-size soil samples and planted the grasses. In just weeks, the toxic chemicals degraded harmlessly into carbon dioxide and water. “It’s a controlled situation to look at how these chemicals break down,” said Yang, the director of the Center of Environmental Sciences at Lincoln University.

The next step, perhaps still a year or two away, is to test the process outdoors.

The researchers are talking with the Army — the initial research has been covered by $110,000 in Defense Department grants — about trying the grasses on already contaminated sites.

Since the grasses are native and grow easily across the Midwest and the Southeast, they pose no threat of kudzu-like exotic species seen as their own environmental threat.

Initial tests show that the amount of RDX in soil is reduced by 50 percent in a matter of weeks, and TNT contamination drops by 95 percent. So, Lerch said, a year or two after planting, a field could be cleaned of the explosives contamination. And the cost might run less than $3,000 per acre.

“If this works, it will be great".

partially sourced ENN news
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Also interesting to note that switchgrass is also a promising third generation cellulosic source for ethanol production and is being researched extensively for that role as well.

Presumably the same process might be operating with a number of other grass species noted as being tolerant to atrazine. This could include a range of common tropical and warm temperate turf species that are tolerant to the herbicide.

Anyone in the Australian military out there that might want to fund a project here in Australia??

Weed Management the BIG Cost to Farmers in Australia

The management of weeds was the major natural resource management activity for Australian farmers, according to figures released yesterday by the Australian Bureau of Statistics.

During the 2006-07 financial year, farmers spent $1.57 billion controlling weeds, which is more than pests ($768 million) and land and soil problems ($649 million) combined, with the total cost of managing these problems $2.99B , or an average of $21,094 per business, ABS reports.

Nationally, nearly two-thirds of farmers reported that they had improved their natural resource management practices. Of these, 89pc reported doing so to increase productivity, 88pc for farm sustainability, and 75pc to improve environmental protection.

Other findings from the ABS include:
* farmers in Australia managed 425 million hectares of land, or just over half (55pc) of Australia's land mass;
* of all expenditure on weed management, nearly two-thirds ($982m) was spent on herbicides;
* of all expenditure on pest management, over half ($430m) was spent on pesticides; and
* erosion was the most common land and soil problem, reported by 48pc of the farmers, followed by soil compaction (43pc) and soil acidity (42pc).

The findings are based on the second Natural Resource Management survey conducted by the ABS.

These findings are an important snapshot of resource management issues in a practical sense. What is not indicated is why the weeds had so much expenditure and does not separate weed control for directly improving production of the land, eg weed control in crops, or is it expenditure on environmental weed control. It does reinforce however, the critical issue of weeds in Australian land management. This is a very significant change in comparison to the older view that insects were the big issue in "land management", including agriculture and natural resource management. It also reinforces the dominant role of herbicides.......but they can also be part of any integrated management system too.

New and Old Herbicides - Tropical Turf

At last...............two new herbicides are available for use in tropical turf areas, especially zoysia turf. They may need to be purchased directly from national suppliers, as unlikely to be stocked in the NT.

The first is Drive - quinclorac is the active ingredient. Been around for a while, starting life as a crop herbicide with the name Facet. Active as both pre and post emergent, so will knock off emerged weeds and add a follow on pre-emerge control. Great for many annual grasses, and a few perennials too. Relatively few trials in the tropics of Australia, but some coming soon. Expect will be useful to control Bahia grass in both couch and zoysia, annual grasses and some hard to manage grass weeds. Will NOT control carpet grass.....period! Currently it is expensive, and in my opinion, very overpriced for an old product. BUT.......for some needs it is a great product and very effective. Has a lot of potential for widespread use in both zoysia and couch areas.

Next is Monument - a sulfonyl urea - and also reasonably pricey, but with the advantage of controlling both sedges and annual grasses in one package, it may be a suitable option. Work locally so far, shows fair results for carpet grass, with medium term suppression and some kill only, but excellent results for sedges and annual grasses. Rates are low - medium, depending on required outcomes, with higher rates required for grasses. Seems promising for tropical Australia.

Old herbicides do not get the advertising $$ once they are out of patent, but they can be effective. The products DSMA and MSMA are still effective for grass weed management in couch ovals or sporting arenas. BUT they need repeated applications, and unfortunately in the tropics it is never cool enough or [ for an oval] dry enough to fully eliminate the grass weeds it seems. They are also relatively poor options for carpet grass control, as they just cannot do the job!

Others though such as diuron and some of the triazenes can be a useful tool, at suitable rates. Be careful though, as some turf species do not tolerate these products.

Asulox will control carpet grass, but rates for use in turf are still to be worked out. It is a sugarcane product and known to have some potential. High rates will kill turf........it will be a balancing act to get rates correct. Currently Asulox is not registered for turf use

Ronstar - oxadiazon - is a very useful but expensive product for weed management while establishing couch or zoysia. Can be effective in Bahia grass, where grass contol options are more limited. Another oldie, but still goodie! Pity prices are still toooooooo high!

A good source of information is www.pestgenie.com.au . A great Australian web site focussing on agrochemicals for the Australian rural scene.

Take care with all agrochemicals and watch out for rain. Remember that in many areas, a good ally is the Met Bureau web site and the local radar. Quickly spots any likely storm clouds. For the Darwin area the link is www.bom.gov.au/weather/nt and go to radar image. Similar links are available in many other areas.

Is carpet grass a weed in your lawn?

Often carpet grass is used as a turf - it is well suited to shaded areas, for example. But more commonly, it appears as a weed in high quality turf areas where removal can be difficult.

Nominally, MSMA and DSMA are used for many grasses as post emergence herbicides. But with carpet grass, it seems as if there is relatively little effect, as it quickly regrows from rhizomes. It is worse in the warmer regions as carpet grass can grow quite quickly, even after spraying.

What is your experience? Is there a reasonable solution that can provide cost effective control of both narrow and broad leaved carpet grass?

Comments welcome.