Author Archives: Ruth

Pollen in the Wind

mobile phone users-you have to scroll to the very bottom to see the right sidebar information

July 2, 2019

I am riding my bike around Wallingford, looking for a couple of big Chestnut (Castanea) trees. I know they are here somewhere. Our lonely Prococe tree needs pollen. I have her male catkins stuck on the end of my bike, in case there is another solo tree out there in need of pollen grains. (Chestnut trees receive pollen from the wind, but the second tree needs to be within a few hundred feet.)

Edible Chestnut trees (not related to Horse Chestnut) need pollen from a different variety in order to pollinate properly. We have two varieties at the orchard … or should I say, had two trees. I am afraid the Maraval is in the bardo. She suffered childhood trauma and maybe that set the stage.

When she was tiny, someone, something, broke the main branch. Without a proper grafting rubber strip, I used a rubber band and put her back together and it worked.

But then, more trauma as a teen. In her third season she was in great health and then, season four, there were bumps all up and down the trunk, and side branches were stubby. Bernie, from Washington Chestnut Company , said some name this ‘bubbly bark’. He suggested I cut the tree way back to just the lower part of the trunk. I did so and, once again, the tree recovered nicely.

Sat, Jul 6, 10-12, Work Party
Sat Jul 20, 10-12, Herb Class
Sun Jul 21, 2-4, Work Party
Sat Aug 3, 10-12, Work Party

At this time of year you can smell a Chestnut tree a block away. I can visualize that intersection. Was it 42nd? The house with the big trees is on a south west corner here somewhere.

Back to the poor Maraval. This spring, she was another casualty of winter moth larvae. They defoliated her whole south side. But, after they gorged and headed for the ground to start a new cycle, she showed some new leaf buds, just like the fruit trees did. Whew, I thought, she will be back. I walked away from her to attend more pressing matters.

But then, things went south. The leaves started to droop despite sufficient water. Then they turned brown. She hung on for dear life until, just recently, nothing green remained. (I hope to blog about her autopsy in the future.)

I spot the Wallingford trees. I snip four mature catkins, push two of them into a clean bag, and attach two others to the back of the bike to wave in the wind.

Back at the orchard, the Prococe Migoule is a picture of health. The styles of the female burs have turned yellow and have spread out across the top of the flower; the tree is ready for pollen. I use the catkin like a paintbrush and lightly touch each female bur. If it’s a success, her burs will grow and have two or three nuts in them this fall.

The pollination period lasts two weeks so I am keeping the catkins on my bike. The more – chestnuts – the merrier.

If you want to learn about the various nut trees you can grow in the Seattle area, there is a rare opportunity to tour Burnt Ridge Nursery. July 20 is sold out but there are still tickets for September 14.

Ruth

Welcome to our Demonstration Garden!

May 14, 2019                                                                                                      DONATIONS PAGE LINK

The fruit trees in the orchard this year would amaze anyone. They are striking and flush …
with pests. It’s true. Come and allow us to demonstrate all manner of pest infestation plus other unsightly disorders.

Last year was a record bounty but, this year, we are counting on one hand the number of fruits from most of the trees.

Why, on one small branch of the Mirabelle plum (photo) you can view tip dieback from brown rot, scale, aphids and leaf roller damage. The pear, just after the height of the leaf roller infestation, has now been chewed to smithereens by the California pear sawfly (photo).

Wander over to the Fuji and notice apple blister mite. Then, check out the powdery mildew on the William’s Pride.

This situation takes me back to coaching where you had to make sure you didn’t spend all of your energy on the one high-maintenance kid and take for granted the other 14 well-behaved teammates. So, yesterday, I coddled our precious persimmon. The persimmon, like the mulberry, sits and watches the devastation and only asks for a drink of water now and then. I composted-in-place its weeds, fed it some nice compost and leaf litter, and laid out a coat of chips on top. Namaste.

Sun, May 19, 2-4, Work Party
Sat, Jun 1, 10-12, Work Party
Sun, Jun 16, 2-4, Work Party
Sat, Jul 6, 10-12, Work Party

Back in February, Allison and I thought we had the winter moth larvae in check. We had banded the trunks then flattened the eggs below the band. The problem was, while we were focused down on that trunk, the winter moth larvae soon would be sailing through the air, landing on whichever fruit or nut tree was within striking distance. Much like a skilled parachutist, I think they tug a certain way on that silken thread to ensure they make it to the canopy. In April, they were landing on our sweaters and hats faster than we could squish them off the leaves and blossoms. We had kept our own trees from propagating larvae but we were defenseless against tall neighboring trees that spit out the little buggers like factories.

Yesterday, I sighed as I cleaned off more dead material from Liberty branches (photo). Oh, but then I looked closely. Was that a little speck of green? Sure enough, the tree is pushing out a new leaf where the others had been eaten.(photo) The Liberty is willing and ready to try again. OK then! We will also find energy to grow and prepare for the next obstacle.

Ruth

Plant Pathogens – Pasteurize? Sterilize? Sanitize? Boil Everything!

March 26, 2019

Recently, I was watching someone rinse a plastic polyethylene plant-potting container in a Brown Rotbleach solution for reuse. I was pretty sure that pot needed to be thoroughly rinsed of organic matter prior to the bleach rinse.

The observation made me think of several reasons why a gardener needs to know how kill plant pathogenic microbes, e.g., effectiveness of our thermal composting process, best product to spray on our pruning shears or, preparation of a previously purposed plastic pot for propagation.

I tried and failed to make a helpful chart. It proved far too difficult, due to so many factors to consider:

varied expressions of quantities
different types of substrates and their porosity
amount of contact time needed
type of organism and state of organism
health hazards
the level of disinfectant desired
shelf life of product
humidity in relation to temperature
corrosiveness
cost of product
where the organism lies and whether you can even get at the bugger

Method

 

Botrytis cinerea (gray mold-fungal) Nectria galligena (apple canker) Weed seed

(sow thistle)

Verticillium dahliae (Verticillium wilt)

 

Pseudomonas syringae pv. tomato (Bacterial speck)
0°F yawn
165°F Dead 1 hr Dead 1 hr
5% sodium hypochlorite (bleach) sol. 2g/liter 20 hr LD90
4%v/v iso. alcohol effective
.3% iodine solution 93% dead 93% dead
Quaternary ammonium 4g/liter 20 hr LD90

Heat destroys microbes best and heat with humidity is even better. However, except during our thermal composting process, heating to 149F for two hours is not practical. As such, I tried to get some answers about products that are available and familiar.

Sat, Apr 6, 10-12, Work Party
Sun Apr 21, 2-4, Work Party
Sat May 4, 10-12, Work Party
Sun May 19, 2-4, Work Party

Let’s start with bleach. Sodium hypochlorite is very reactive, affected by surface contamination from organic matter and it’s irritating to use. It’s difficult to know what dose to use and, at the concentrations that many people use, it leaves a residue on the surface. (1000 ppm will destroy all microbial pathogens but for the tough resting spores. Using household bleach (5.25% sodium hypochlorite), the dilution would be 1:50 or 5T per gallon.)

Ethanol (think Everclear) can kill most organisms but it is highly flammable and evaporates quickly. It dries out the organism (which is why the similar product, isopropyl alcohol, is better as a disinfectant for the skin). Alcohols reportedly won’t kill some spores and they harden rubber and some plastics on tools.

I could not get a clear idea whether hydrogen peroxide is a good pathogen hunter. Articles refer to its effectiveness, especially on inanimate surfaces, but indicate that hydrogen dioxide is a superior disinfectant on plant production surfaces.

Quaternary ammonium chloride. Hmm. There is a lot of controversy about Quats and they are reported to be not always effective against the tough customer – the fungal resting spores.

This brings me to a possible unsung hero – iodine. Remember when you went camping where the water was bad. You mixed the two tablets in water and waited. That second tablet helps with the discoloring and the taste and also is a solubilizing agent. One potential downside is shelf life – about five years.

A flameless loop sterilizer might be the ultimate tool but not readily available and you would need a power source. (We will leave out solarization, which, for the time being anyway, might be challenging in Western Washington.)

This study is way more complex that I could have ever imagined. There is no one size fits all solution. Shown here is a popular chart from two State of Washington professors (who are also fine authors of plant pathology books).

Good reads:
Investigation on the fungitoxic effect of an iodine solution on three plant pathogens in vitro. Bengt Boysen.
Bachelor project in the Danish-Swedish Horticulture programme
2004-1 (ISSN 1652-1579)

Time and Temperature Requirements for Weed Seed Thermal Death
Ruth M. Dahlquist, Timothy S. Prather, and James J. Stapleton
Weed Science 2007 55:619–625

Soil Solarization and Thermal Death: A Logarithmic Relationship Between Time and Temperature for Four Soilborne Plant Pathogens.
G.S. Pullman, J.E. DeVay and R.H. Garber
American Phytopathological Society, Vol 71, No. 9, 1981 p 959

Temperatures Necessary to Kill Fungi in Wood
USDA Technical Note 259, Forest Products Lab Feb 1956

Safe Procurement and Production Manual A Systems Approach for the Production of Healthy Nursery Stock
Griesbach J., Parke, J.L., Oregon Association of Nurseries, January 2012
https://www.researchgate.net/publication/282649506

Dose Curves of Disinfectants Applied to Plant Production Surfaces to Control Botrytis cinerea
W.E. Copes, Plant Disease-American Phytopathological Society, May 2004

Chemical Disinfectants
https://www.cdc.gov/infectioncontrol/guidelines/disinfection/disinfection-methods/chemical.html

Quaternary Ammonium Compounds
Quaternary ammonium compounds are the most commonly employed broad-spectrum hard surface disinfectants employed in animal research facilities.
From: Laboratory Animal Medicine (Third Edition), 2015
https://www.sciencedirect.com/topics/neuroscience/quaternary-ammonium-compounds

EPA Hard Surface Disinfectants
https://www.education.nh.gov/instruction/school_health/documents/disinfectants.pdf

Ruth