Good morning people.
Looking back at earlier messages, Collin asked why we should not hollow core more than once in three years. Well, one good reason not to, (if you have three greens to look after, as I do), is that it's a big job and one green a year is enough. Unfortunately, I'm having to scarify, core and dress all three this year, and it is taking for ever.
What I have noticed though, is that the core holes are approximately three inches deep, but the cores are much shorter than three inches long - perhaps only an inch. I'm wondering if A: the cores are compressed, B: the rootzone beneath the core holes is compressed or C: the top three inches of the green are mainly air. The particular green that I was coring yesterday is in a very bad state, and I have noticed that the cores can be longest around the edges where there is more compaction.
I'm also looking at the idea of incorporating seaweed meal into the cored rootzone before dressing, but am now confused by what the salesmen say on the subject of seaweed. There is heat treated and non-heat treated.
Any thoughts?
Peter
Ok Head Tea Boy, prepare to be immersed into this great subject of seaweed.
Seaweed meal is dried and shredded seaweed and is not subjected to either of the hot or cold processes mentioned above. What is important is the species, the composting process and the particle size of the meal.
Species: research constantly highlights the species Ascophylum nodosum as having the most benefit for turf use. This species grows in the intertidal region of the shore line and has to withstand all the environmental stresses that go with being drowned twice a day, battered by waves, and exposed to drying air, as the tides come in and recedes. Other seaweeds just float or wave around in deep water and do not possess in any great numbers the group of hormones, called Betaines, that enable Ascophylum spp. to withstand these stresses. All seaweeds have to absorb nutrients from sea water by using another group of hormones called Cytokinins.
There are three, possibly four, processes in extracting the liquid from seaweed: 1. a hot process involving boiling up with chemicals that kills off many of the hormones and vitamins that make seaweed so beneficial for turf. These products are normally very cheap but have a very high application rate. 2. a cold press process that retains many of the hormones and vitamins, but also during which some are lost. All the good seaweed liquids are cold processed. 3. and 4 involve a freezing process. The best I have experienced is a seaweed that, broadly speaking, is flash frozen to -50 C which destroys the tissue and after melting the liquid is sieved off. The company claims100% retention of all the hormones and vitamins that make seaweed so good for turf.
On application, the main benefit of seaweed is the hormones moving nutrients from the leaf to the roots. When roots require nutrients a signal is sent to the leaf where nutrients are stored. Hormonal action sends the nutrients down but are often captured at the growing point - the area of highest demand for energy and nutrients for leaf growth. The result is a dying back of roots during the summer. Seaweed provides the extra hormones that enables nutrients to get past the growing point and into the roots. Results - larger root mass. This is why seaweed is proving so useful for nematode resistance. The grass has much more root to stop nematode damage from affecting growth.
Betaines help by enabling turf to withstand environmental stresses such as heat and cold.
We could go on but I have a garden to tidy and I am sure others would want to contribute - Mark Atkins for one! I hope this stimulates some further study.
Best regards
Andy Turnbull
31 Oct 2009 by Anthony Asquith
Totally agree with Andy on this one, Some research has shown that cold extracted seaweed is more beneficial to turf as all the valuable goodness is retained ie algnic acid, hormones, vitamins etc. A key point like Andy says is that Betaines, phytohormones etc reduce stresses on the foilage and increase the stress tolerance levels.
The algnic acid by the way improves the moisture retantion of soils as AA acid increases the formation of good soil structure and stabalize it further.
Cheers
Ant
Many thanks for that immersion in the subject of seaweed, very refreshing.
It just goes to show that we don't only have to understand about turf care to do this job, but we also have to understand the mind and language of salesmen.
I have been told by one company that seaweed extract is fantastic - so I used their product for years, now I am told by another company that only green (rather than black) seaweed extract is fantastic, and that the other stuff is a byproduct of the cosmetics industry. Two companies that have offered me seaweed meal are based in Ireland, and I imagine that their product is the tide-washed algae that you write about. I bought a bag from Saltex a couple of years ago, to try out on a garden lawn, and found it to be extremely dirty. A very fine, dusty product. You write that particle size is important, but you don't say which is better - fine or course.
I am looking to use meal rather than liquid, partly because all of my greens are hollow cored at the moment and it seems like a good opportunity to give them a shot in the arm - so to speak, but also because I'd like to simplify my summer feeding programme. One salesman said that a twice yearly meal application would be an alternative to monthly liquid applications during the summer.
With regards the hollow coring, I think I have answered my own question. I finished coring the third green yesterday and noticed that less and less material was being taken out of the green, but the hole depth was still deep. On examining the tines (which were new when I started the first green), I found that they had worn considerably. When new, there was a relatively thick tine wall at the cutting point, which would compress the core slightly and allow it to expand again once it had entered the main body of the tine. However, once that section of the tine had worn away, there was no room for expansion in the tine and the plug would be gripped, thus reducing upward movement.
Taking the tine out of the machine and pushing it into the green by hand, I noticed that less than an inch of rootzone went into the tine, but the tine could still be pushed down a long way. So, rather than opening up my greens and allowing for soil exchange, I have compressed them.
I only hope that this compression will be relieved by winter frosts (if we get any).
Many thanks again,
Peter
Head Tea Boy
The best quality seaweed meal available in the UK comes from the west coast of Ireland due to the pollution free waters. Seaweed from the west coast of Scotland is too contaminated to be used in cattle feed due to the risk of contamination from salmon farms entering the food chain. Have a look at www.arramara.ie for more info on green and brown seaweeds.
Whether liquid or meal is your choice and preference. I would prefer a fine particle size as it is easier to brush into holes. Some have used uncomposted meal and it turns to a gel before breaking down. Composted seaweed will brush in very easily if dry.
You make some good points about hollow coring. It may be worth spending more on better quality tines, but I have found that heave action, eg Verti-drain, is the only way to relieve compaction, with coring helping to control organic matter and to get air into the surface.
Best regards
Andy Turnbull
Back to Top - Go to Next Unread Message
This Message is closed, you may not post a reply at this time