By Kyra Fielden – Grower Services Bay of Plenty
Harvesting is well underway in the Bay of Plenty even with dry matter clearances being a bit random this season due to early harvesting expectations, making the harvest plan turn upside down on a weekly basis.
However, the Just Avocados crew are doing a stellar job at keeping up and making changes where necessary to ensure a smooth and trouble-free harvest.
Rainfall around harvest is a hot topic in this newsletter – something growers might like to do is have your own rain gauge and record daily rainfall 1-2 weeks leading into your harvest date.
Rainfall throughout the bay can be varied so it pays to know what level of rainfall your particular site is getting and if in doubt carry out a roll test prior to harvest – ask me if you want to know how to do this.
Overall, trees are looking pretty healthy so far but as more stress comes on as flower buds extend, the trees will require an extra boost of nutrients and support.
Foliar feeding can play an important role at this time of year when tree roots might not be working to optimum levels in cold and wet conditions.
To find out how prepared your trees are, we can take leaf samples from your trees and our technical manager, Erica Faber can tailor a three-month foliar programme specific to your orchard or we have a standard prefoliar combination boost we can advise to go in with your next chemical application to support trees.
Out and about on orchards over the last few months, growers have been observing various mushrooms popping up underfoot, a sign of fungal activity in the soil or mulch layer. Mushrooms are like the tip on an iceberg in the soil as they are the fruiting bodies of fungi designed to produce spores for reproduction.
I’m writing about fungi because growers are asking ‘What are they called?’, ‘Is it okay to have mushrooms growing under my trees?’.
There are over 100,000 different kinds of fungi known, and many more yet to be discovered.
Avocado trees require high levels of organic matter and soil fungi to improve uptake of nutrients and moisture through their roots and to increase soil aeration for disease suppression. The more beneficial fungi we have the better they can out compete the pathogenic species.
FASCINATING FACTS ABOUT SOIL FUNGI
- Fungi have very fine hair like strands called hyphae that are microscopic and can’t be seen by the naked eye, a teaspoon of healthy biologically active soil can have several yards of fungal hyphae in it.
- Fungal hyphae are significantly smaller and many more of them than tree roots so can reach a larger surface area of the soil gaining access to more nutrients and moisture than roots alone can.
- Nutrients are absorbed by fungi and immobilized and not lost or leached out in the soil then later released.
- Mycorrhiza fungi get special mention as they will transport nutrients and water back to plant roots they are connected and attracted to via the root exudates, a fine trade where the fungi has a mutualistic relationship with the tree and receives carbon from the tree root exudates and the tree receives nutrients and water from the fungi.
- Fungi are saprophytic where their decay breaks down dead organic matter like woody material and leaf litter and have the ability to transport nutrients back to the root zone, proving why it’s so beneficial to chip your prunings back under your trees, utilising the nutrients it has taken to grow those branches.
- Aerated soil encourages more beneficial fungi, pathogenic fungi can withstand anaerobic conditions. When fungal hyphae die, they release nutrients and leave tunnels for other soil biology like bacteria and water to move through and live in, creating more aeration, forming the crumb like structure of soil helping to supress disease.
So, YES! It is ok for mushrooms to pop up in your orchard—in fact the more diverse species you see, the better and they may even be Mycorrhiza!
You don’t have to know their names but they are intriguing, if you wish to learn more, here is a link to a fungal guide that might help identify mushrooms from fungi popping up in your orchard: https://fungalguide.landcareresearch.co.nz/WebForms/FG_Home.aspx