Using Friendly Mold As an Herbicide Part a and B and C.

Introduction: Using Friendly Mold As an Herbicide Part a and B and C.

Using Mold to kill plants like Poison ivy, and other weeds.


Penicillium Italium is a level 2 plant pathogenic and very low harm to humans. If it can be dosed and used properly it kills on contact different types of weeds.

Although the risk is low for pathogenic molds here are some warnings on plating. I recommend using plates to grow the mold. If you see the following mold expose the sealed plate in 10% bleach to kill the spores, mold and toxins for 3 weeks.

Red mold = Penicillium marneffei.

Black Mold (completely Black) = Aspergillus fumigatus.

Wearing an N95 mask when you are isolating the fungi is CRITICAL. I repeat critical.

You can grow mold from a lemon in an anaerobic condition sealed and with an N95 mask add it to soap and centrifuged it to remove 99% spores. The spores release an activating enzyme called Pectinase. An N95 Mask is a kind of necessary to limit your exposure to this mold. Unlike some molds that are toxic PI is not considered toxic or severely allergenic but precautions with a mold must be in place.

The mold is added to tin chloride to burn the clover with ammonia and lye to allow for it to slowly grow on the plants. The bleach breaks down into sodium chloride and oxygen later on. Also, the bleach or TCCA actually destroys 99% of the mold causing some to go dormant and if the plant tries to regrow than the solution with mold will through the soil enter the roots and destroy it. (Theory). Also, molds like this can live without oxygen so this is a bonus (In the soil).

Lasers and High voltage have been tried to burn the spores in the past to try to release spores enzymes but it failed. Even 12 kV 30 mA had no real effect.

Part A.

INTRO: Molds like PI are directly pathogenic to plants but low risk to humans. I have tested this mold on clover and it killed some clover seeds from growing while others developed resistance. This is why TCCA or bleach eventually should have been added but it was done in the garage. I wanted to test what would happen if mold grew 0.1 mm between each clover. It was slow and it took 2-3 weeks at 40,000 spores per ml (Approx) in the culture. I did a test to determine the growth by slowing it down in the fridge.

Purpose: Is to determine if Mold with chemicals can kill plants effectively.

Calculation: Similar pencillium in 5 days grow 1 billion spores min.

10 billion *4/1000 ml = 40 million cultures per ml *1/100 = 400,000 cultures of PI.

y = 8,333,333X+ 400,000

Time (Hrs) (Mold spores) PI. 400,000 spores 0 hrs 20,000,000 spores 24 hrs. 39,000,000 spores 48 hrs. 60,000,000 spores 72 hrs.


Take a Lemon and seal it in an area with the growing mold from the fridge. In a tub aware device close off the oxygen yes Mold can grow without oxygen too and let it incubate for 13 days or so. A slightly better method is to cut cheese and place pre-existing mold spores (Outside with a mask) on the cheese as it soaked a bit with water. It may take one to two weeks with light (Key) to grow the mold.

Here is an alternative.

Go outside and wear an N95 Mask, Goggles, and gloves and place the spores that you collected until you get on a digital scale 5.00 grams of mold. Place this into a flask with a magnetic stirrer with 10 g TCCA per L and 10 g Lye. This solution is very caustic and emits chlorine it must be done in a well-ventilated area!! Have the device stir for 2 days and allow the bleach to partially digest the material. Then add concentrated citric acid to neutralize the Lye and concentrated sodium thiosulfate until the pH is 7.0 or under.

In a centrifuge tube pipette 1.5 ml of sample for 8 tubes and centrifuge for 30 minutes. This removes 99% of the spores as a pellet and causes 1% of the pellet to remain.

Pour the 1 ml sample now measuring that into a solution 1 L of water with sodium carbonate to attack the plants with some tin chloride (1 g max). This helps create a colloid that damages the plant long term.

Add bleach carefully diluted by 1/5 to a 5% concentration of the plants and this will kill the weed.

After 20-30 min the spores multiply each time. A couple million spores per plant would be typical for this mold on the plant. Also, humidity, air flow (especially) outside would affect the growth of the mold on the plant. As well the type of plant and its metabolism is essential for the mold. While it could be tested on Poison ivy more resistance could occur and higher doses of bleach 5-10% equiv may be needed.

Here is a centrifuge instruction although mine is simpler design it still follows similar protocols.

I grew the fungi on cocoa agar that took 2-3 weeks in a sealed container and added to a 500 ml flask approx 250 ml of 5% TCCA with lye to digest the mold and did this for a week on stirring. Then acetic acid to neutralize the lye and sodium thiosulfate was added to neutralize safely the chlorine. The samples of 1.5 ml were centrifuged for 210,000 rotations per minute total to remove a huge percentage of the mold most of it (the mold) was trapped on the bottom of the centrifuge tube as a pellet.

Here a video on bleach 5% compared to control and it does alone kill the weeds. If you wanted to kill poison ivy you would need to spray 2% bleach on the poison ivy for two weeks then kill the plant with spores from PI. Bonus bleach is quickly degraded by bacteria, etc in the soil and converted into oxygen and sodium chloride.

2NaoCl(aq) >>>> 2NaCl(aq) + O2(g).

The fresh soil was added with clover and 1 ml of sample was added to a small amount to give approx 40,000 spores per ml. It was sprayed very carefully on each clover. A grow light to stimulate light and day and it took 2-3 weeks for the mold to grow in the clover. Oddly some clover died while other did not. They grew fully and resisted the mold!! Each clover bed had 50 clover or so. There were 50 of them (clover beds individuals) so 2500 clover plants.

The advantages of using this mold are that it is very stable capable of lasting years as it goes dormant~!!! It can grow in oxygen and non-oxygen atmospheres.

For 1 L about 5 ml of spores were added to 10 g of tin (II) chloride with ammonia and other stuff to form a spore colloid. It quickly creates hydrochloric acid and some tin to burn the plants allowing the fungi to enter the plant. It is tested on wild plants in the front to see what happens to them. Bleach or TCCA would be added to it that damages the spores and the cell structure of the plant. Some mold will penetrate the soil and the roots and stem killing the plant.

Part B explains the added bonus of adding soap and sugar to the mold mixture to encourage growth faster than normal and keeping in moisture. This reduces the air born spores allowing for the addition of bleach 4-8% to kill the plant and the remaining spores.

Part C uses sugar and a higher 6 times higher dose of the mold through the control of the centrifuge.

Advantages of using Mold:

A safe bio herbicide that is low pathogenicity to humans unless in very very large amounts for a long period of time.

A Very stable compound will not break down in soil and loose effect.

Fairly easy to grow ( the mold).

Can be added to soaps or acids to weaken the plant structure of tough plants like Poison Ivy.


May have an unknown effect and chemicals may reduce natural flora of bacteria in the soil. It could take longer for the soil to recover.

The bleach spray could have an impact on bees and wasps but I checked this out by sitting outside for 30 min and the seem to be repelled by the pool smell. Low risk in my opinon.

Here I have built a crude light meter attached to a 15 W light (Incandescent) and a slit. In a controlled area, I measured the ratio of light produced by a control compared to full strength.

At 210,000 Rpm and with a special medium I reduced the mold by 99% by centrifuging. Y = 4.75*10^-4X. Where Y equals Total Percentage of mold t and X equals the Rotation per minute total.

So 5 minutes or 35,000 rpm total equals a removal of 16.6% of mold.

Note that weed whacking Poison ivy, etc without proper PPE is NOT RECOMMENDED as the toxic oil may spray you in the face blinding you or if it lands on the skin it can cause severe burns. Also, the oil is highly resistant and takes a long long time to break down. Here some alternatives if you don't want to mess with mold.

Large doses have the possibility (slight) of an allergic reaction in some cases.

Part C: Using a total of 400,000 spores *6 to give 2.4 million each and observing them on simple plants like grass.

Although I don't recommend Round up due to the toxic and possibly cancerous effects on animals and maybe humans it can be used as a last resort. I don't know how well Mold with chemicals would affect poison ivy?

High resistance to normal chemicals in the past at my old property made it difficult to kill it. You must target the roots and they can grow several feet under the ground. Right now I have exposed plants with high doses of the mold with bleach and it is working.

This is still on going I will edit it when more info comes 2-3 weeks later. A lot of info is known from Microbiology at Algonquin and Water and waste management program at Algonquin. After a week the mold with chemicals prevented the growth of weeds (it killed the weeds).

Testing plants outside with the same concentration at 10% mold growth mixture and I will see what happens in a couple weeks it also contains 6% acetic acid and oils (Vegetable oils). Plants like grass and ones with simple roots will be easier to target with this method while tough weeds with big roots like Burdock or Poison ivy would be quite tough.

Here some info about an alternative Penicillium D that could be used instead. Please see references for more details. spores of PI under the microscope at 1000 X *1.5 with methylene blue dye.

For both steps Part A and B it possible to scale it up with a centrifuge at 4000 RPM that can hold 20 ml *6 samples for bigger cultures of weeds, etc.

This with the centrifuges may only cost 100 dollars US compared to 300 dollars US.

Part B: Adding enhancers like soap and sugar to encourage the mold to grow more rapidly on exposure to the desired plants. The mold plus 8% bleach on other plants like burddock had no real harmful effect. However the st. Johns wart did have a effect it killed the st. johns wart.

Part C adding a total of 2.4 million spores per sample spray to grass and catnip mint plant. The high sugars, etc encouraged the mold to grow faster (a few days faster) and allowed the bleach to target the mint faster.


Hine, Richard. "Blue and Green Fruit Molds". Diseases of Citrus in Arizona. The University of Arizona. Retrieved 19 October 2012.

Onions, A.H.S. "Penicillium digitatum. C.M.I. Descriptions of Fungi and Bacteria No. 96". Descriptions of Fungi and Bacteria. CAB International Wallingford UK.

Fergus, Charles L. (1952-03-01). "The Nutrition of Penicillium digitatum Sacc.". Mycologia. 44 (2): 183–199. JSTOR 4547585.

Samson, Robert A; Pitt, John I (2000). Integration of Modern Taxonomic Methods for Penicillium and Aspergillus Classification. Amsterdam, The Netherlands: Harwood Acad. Publ. p. 23. ISBN 9058231593.

Holmes, GJ; Eckert, JW (1999). "Sensitivity of Penicillium digitatum and P. italicum to Postharvest Citrus Fungicides in California". Phytopathology. 89: 716–21. PMID 18944698. doi:10.1094/PHYTO.1999.89.9.716.

Discussion: After 1 week the Mold started growing on the clover and there was evidence that it can kill plants. Higher concentrations of 10-15% or greater of Mold may be required. A 1% solution was very effective but took a few weeks. A 6X concentration will kill clover and other weeds much faster. As seen in the final image PI actually inhibit growth by breaking down the cell wall of the plant and roots. However another factor it blocks light from reaching the plant too. Most corrosive to plants is bleach since it produces sodium hydroxide and hypochlorous acid. The latter actually attacks DNA of the cell, destroys protein, interferes with metabolism, and attacks the cell wall of the plant. This plus the mold would increase the death rate of the plant. In terms of using sugar 5 g per 100 ml with spores to enhance the growth of the mold is an Option.


The final image on random weeds in my back yard indicates that the mold slows down the growth while the bleach burns the plant. Small amounts of the spores resist the bleach and if the seeds or roots try to re grow this method should prevent it from occurring due to two things: 1. The mold interferes with auxins, cytokinins, etc and digests the cell wall and the bleach burns the plant and bio remediates and converts into salt and oxygen. The final image proves this can work as a herbicide. More testing must be done to see how compatible it is with tougher weeds like Burdock. Mold can grow faster if sugar is added to the mix when sprayed.

The burdock even with two treatments of bleach and one treatment of mold/sugar did resist to a certain percentage of the plant. I will check it in a week to see what happens.

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    Tip 1 year ago

    Making potassium bisuth iodide to the culture may cause it to grow faster. Here a video on how to make it. I mixed bisuth oxide with dilute HCl and Potassium iodide with KOH.