Undiluted Neem Oil in tree paste application?

  • May 11, 2024 at 8:39 am #1933
    Jon Place
    Participant

    Hello forum members, Has anyone used pure neem oil (without soap emulsification) in their tree paste applications / as an applicant directly to tree bark? My sprayer is down currently, and I am trying to think of creative ways to use and apply my neem oil. I am considering mixing as is without emulsifying into a tree paste formula. I have vague memories of this being discussed and trialed by orchardists active on the forum… ring a bell for anyone? Just want to verify before possibly doing something that my trees may not appreciate… Thanks! Jon Place (Rutland County, VT)

    May 11, 2024 at 9:19 am #1934
    pomologydude
    Participant

    Hi Jon,
    I have tried various oil products in my tree paste and yes neem oil can work when mixed properly with the other ingredients and diluted with 508. I can’t remember the exact proportions, but typically I will put 10% by volume of “anything else” in the mixture. So if the base mix is manure (or 500), sand, and clay 30/30/30, then the last 10% can be neem paste. It can be less of course. That said, I am not aware of anyone that has compared various concentrations for efficacy. But for general tree health, 10% is a good starting point.
    mike

    May 11, 2024 at 11:24 am #1935
    Josh Willis
    Participant

    Jon, I have notes and memory that Michael recommended applying a 100% neem via brush or (if solidified) butter knife as borer protection to the bottom ~4-6″ of a tree trunk. I can’t find the exact reference, though he does talk about it a bit in the June 2016 newsletter. In any case, I’ve done this on our handful of peach trees that are prone to borer, and they have been just fine. Keep in mind that I think young trees do absorb nutrients through thin bark, so that might be good to double check if younger trees are ok with such a paste.

    If you are talking about tree paste as a rejuvenating treatment for bark health, then in addition to Mike’s post, I’d recommend looking at the forum posts for tree paste formulations, there are some very good discussions. If you do want to reduce 100% neem to a lesser percentage, presumably some emulsification is helpful actually standardize the mix, i.e., to have some fidelity to the formulation you are trying to achieve.

    Keep in mind that I think there is sometimes a fine line between a high enough percent of fatty acids to disrupt microbial activity and enough to encourage microbial activity. For example, the difference between a “Fatty Acid Knockdown” (perhaps at 4% Neem) and an inoculating spray (at 0.5% or 1%). I’m guessing for a band on the trunk base, that is less of an issue, but for a broad swath of the trunk and branch structure, that might be more of a consideration. Hopefully somebody with a better understanding of microbial activity and fatty acid percentages can chime in here to better elucidate.

    May 11, 2024 at 12:10 pm #1936
    Josh Willis
    Participant

    To satiate my own memory, and whether it is truly there, I found Michael’s discussion of painting pure neem. This is actually in the Winter 2022 newsletter. Here’s an excerpt, check out the newsletter for more discussion.

    “Those of you caught up in borer karma should know a number of us have had good success with the “direct neem plan” for borer on young trees. The idea being to paint undiluted neem oil on the lower eight inches of small diameter trunks—even allowing it to puddle up at the soil line—someme in May/June before female adults begin to oviposit. This preemptive treatment does the job for the full season ahead.”

    May 11, 2024 at 2:11 pm #1937
    pomologydude
    Participant

    The biod trees paste that I use (as described above) is to encourage beneficial microbial activity both for the health of the tree in its own right but also through competitive colonization to discourage pathogens. The Bd500 has microbes in it that can grow and expand on the tree with the assistance of the neem. But yes there is a fine line between too much and just enough, but I don’t think there is ever too little. As far as borers, I have used pure neem (like putting butter on bread) as a preventative, but also as a curative after damage has occurred. It works really well in both situations. However, one caveat, is that too much or too many years in a row and it appears that there can be some minor (or major) trunk damage. Not sure why this is the case, but it is an observation. So, I encourage others to space out applications (but don’t space out on the applications – lol) to every other year. I think the paste suffocates the lenticels in the area of the application causing mortality.

    May 11, 2024 at 5:45 pm #1938
    Jon Place
    Participant

    Awesome, nice work locating Michael’s reference!! Thanks everyone for the timely insights, particularly with the BD approach included. Best of luck to everyone in the orchards! Gratefully, Jon

You must be logged in to reply to this topic.