After much hand wringing and tears, I decided to have my old (not good fruit bearing) avocado tree removed. Boy do I miss it's shade already! While the men were at it, they also removed a cactus and bird of paradise. It was a quick and dirty job, all 3 plants were down, ground out and hauled off in under 3 hours! I could not believe it. Now, I'm left with an empty back yard and tons of large and small wood chips in the soil , not to mention everything is very drought weary. My question is do I need to remove all the wood chips before I plant my little 5 gallon avocado? I know I'm to amend the hole and back fill soil, but do you think that the wood chips left throughout will rob the avocado of nitrogen as it decomposes? Thank you for your input.
I'd suggest adding a little manure to the stump grinder's fine wood chips and sawdust to both add nitrogen and help the woodchips to break down into humus more quickly. You are right in that soil organisms breaking down the fine mulch use a considerable amount of nitrogen. The woodchips will then add N to the soil themselves, as you know. The larger wood chips from the woodchipper, on the other hand, will take a long time (months+) to break down, so only a little nitrogen will be depleted every day until they are also returning it. Bear in mind too much nitrogen leads to less fruiting. Since your last tree had this issue, you might want to consider testing your soil's nitrogen content. You mention you are in drought. The mulch will reduce water evaporation, otherwise a major factor in loss of soil water.
Thanks for your input BT. I planted my little tree yesterday, but picked a spot a few yards away from the original location as not to have to deal with all the wood chips. I added a bag of amendment (can't get too much bat guano can we ) and mixed in some of the various soil from the removal sites. So there is a fair amount of organic matter from the grinder. Our ground is like rock due to the drought, but at least the little tree will have a fighting chance.
