Aeration and infiltration
Tomorrow, Monday the 22nd of June will be our summer aeration window on the putting greens at Phoenix golf club. We have done no major aeration since our hollow core just before lock-down and its well over due. We had certain restrictions placed on us from the R&A and England golf, some of which I didn't agree with but nether the less best not to upset anyone, especially as I'm avid twitter poster, too many eyes watching 👀.
Since reopening of the golf course the traffic has been immense, lots of play from members, visitors and squeezing extra large field competitions in has its detrimental effect on the compaction of the greens and ultimately infiltration of water. (below is the results of the last test, you can spot our suspect greens!!).
Infiltration is measured in mm/hour and is the rate at which soil can allow water to move into and through the soil profile, this allows the soil to store the water for plants and soil biology but also release excess water. Sandy soils infiltrate water fast and so release nutrients fast this is called leaching, clay soils infiltrate really slow compared and really need help to get things moving. Plenty of aeration at varying depths and topdressing with pure sand helps to speed this infiltration up. The aeration, especially deep with a vertidrain, really creates cracks and fissures below the existing root line and the extra air that is imparted deep down will encourage the roots down deeper to tap for more water and nutrients. Our upper profile has a very high percentage of sand but that is sat on a poor draining clay sub surface, so the more deeper aeration we do the better. The surprise from my tests was the 10th green, we've had massive problems with that green but after the oxyshot demo that blast air to break the subsoil, we have definitely seen a big improvement, maybe evidence we need our own or we need to hire one more often!
The STRI and other experts in the field will have fancy expensive equipment to measure infiltration rate, but as we don't have access to such tools I plagiarised another greenkeepers technique, us greenkeepers do like sharing ideas on twitter!. So the idea is to use old hole changer blades as a tool to measure the rate your soil peculates or infiltrates the water. Is it accurate?, no where near! but it gives you a consistent reading ready to compare. I know the important parts of my roots will go no deeper than 6 inch if we are lucky with Poa Annua grass and a clay subsoil, so we knock the hole blade in to that depth fill with water and measure the amount of water drop in mm in a given time frame.
My whole programme differs a lot from previous years, I'm concentrating on the soil food web. This is the symbiosis between mycorrhizal fungi, bacteria, protozoa and nematodes to work as a team with the soil and the plant. They all actually eat and attack each other but a balance is met and these micro-organisms like bacteria Azobacter, Bacilluss subtilis and fungi Trichoderma unlock soil nutrients for the grass plant, gather and stick to plant roots and protect the plant from nasty pathogens like microdochium nivale (fusarium) and Colletotrichum cereale (anthracnose) and in return these mycorrizal organisms get a tasty treat from the plant as the the grass releases sugars as exudates from the roots. This programme actually means I spend less money on feed as the microbes are releasing nutrients for me by breaking down thatch into available forms, It can take a few years to fully get going but I'm seeing results already after 12 months. So if you see me say compost tea spraying, thats the mycorrhizal tea I've brewed for 36-48 hours in a home made compost tea brewer.
So the plan is to Verticut the greens to remove some organic matter, remove Poa seed heads, open up the canopy to some air & light and also aid infiltration from the surface, cut the greens then Vertidrain with 13mm tines to a depth of 8 or 9 inches then topdress with sand and brush this into holes, sarrel roll then Iron to smooth the surface ready for play. I say ready for you to play, you can still play between all these processes although once the vertidrain is on the green please pick up and walk to next tee, this is a long process and you will hold play behind you if you wait!!. There will be no temporary greens as we are only on one green at a time with the vertidrain and the other processes are quicker and you can play once the greenkeepers have left the green.
Thanks for reading here’s to another successful summers golf at Phoenix