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Wildfire Impact on Farming in Washington

Learn more about how apples get bogged down in the smoke and livestock are affected by the fires

Orchard impacted by Bridgeport WA area fires last week

If you live in Washington State or any of the surrounding states, we're sure you're fully aware the immense amounts of smoke in the air. With about 5 millions of acres that have already been burned and thousands still on fire in the states of Washington, Oregon, and California, we just wanted to take a moment to inform you that not only your air quality but also the production of food sources can be drastically affected by the tremendous amounts of smoke. To put things in perspective, one of our employees was recently in the State of Michigan and the smoke from these three states has already made it halfway across the country and over 2,000 miles away.

According to an article written by, the Washington Apple Commission "predicts a 5-10% reduction in crop volume for Washington apples due to recent weather." It's not only the amount of smoke that's affecting crop production but the combination of smoke and

No Power = No Water

wind that has been the awful hinderance to growers trying to maximize crop yields with the recent increase of demand as consumers have been inclined to eat healthier and buy in bulk to avoid grocery stores. This odd combination of wind and smoke has resulted in apples being tossed off of trees, damage done to equipment and trellis systems, and some growers to delay harvesting.

With the State of Washington producing about 58% of the nation's apples, with about 10-12 billion apples harvested each year, enough to circle the earth 29 times, we need to make sure that we support our local orchards and give them any sort of support they can get.


Hermann G. Thoennissen:

Hermann G. Thoennissen (affectionately known as Herman The German) is a friend of with deep expertise in orchard development & management, employee training, and business transition. With 35+ years of experience in various orchard management positions in WA State, 30+ years as the owner of HTG International LLC., 20+ years of experience in using aerial imagery in permanent crop production and also being an active team member of FarmCloud since 2012, Hermann provides consulting services to some of the largest organizations in the global Tree fruit and Ag industry in the western US and China. is happy to share exclusive access to Hermann's research notes on the effects of the fires in Washington State.

Hermann's Research Note:

Solar radiation readings at the WSU Ag WeatherNet Pasco Badger Canyon Station:

on Sep 1 it was 20 MJ/m2

on Sept 7 it was 8,

on Sep 12 it was 7,

on Sep 13 it was 5

Evaporation rates responded accordingly. Air temps did not drop as much, however they too dropped slowly.

The forecast as of noon Sep 14-2020 indicates at least three more days where the smoke will lower the light conditions to levels near those of today.

Plants need good, direct light for development and finishing of fruit and also for building reserves for the already formed flower buds for the 2021 crop. Heavy stress can cause deformities and in severe cases abortion of these flower buds.

When observing the trees at multiple locations throughout the lower Columbia Basin and parts of the Yakima Valley here is how I can sum it up:

The trees do not look happy.

The trees -clearly visible on the foliage- are under stress. Leaves have curled the outer edges downward, a clear indication of stress. This is a reduction of leaf surface exposed to the sun, thus reduced photosynthetic potential. One must add the amount of dust/ash residue on the leaf surface further reducing photosynthesis.

When trees are under stress, they release ethylene a gas that has multiple functions in plants. When released at this time of season it moves fruit maturity forward rapidly. However, with not even the basics of photosynthesis being covered by sunlight the trees are not actively producing carbohydrates. Color development is at minimum impeded as the biological pathways for it are not active. 

As a result, the fruit on the trees will not mature normal. Depending on its stage of maturity and the number of days from anticipated harvest the reaction of the tree varies by variety. 

All these events will make decisions for the farm managers and others involved in maturity evaluation extremely difficult.

For some varieties the first pick has been completed.  The second pick does not have sufficient photosynthesis to advance the remaining fruit to desirable good or optimum color.

A few colleagues and I have observed the variety Honeycrisp that had first pick 6-9 days ago and the color development on the remaining fruit is very slow. However, fruit firmness is dropping pretty much at the same rate as it normally does (this process is less dependent of photosynthetic activity).

Varieties that are near or at first pick are slow to finishing to good color for first pick. Color development for the second pick will most likely be very slow if it takes place at all. 

We had a similar situation about three years ago -during the Okanogan fires- they however were earlier and the light reduction was less severe and not this many days.

As for ongoing harvest operations I suggest that we be guided by internal values more than by color. There will be fruit that will meet internal standards; however, color will be marginal.


To take Hermann's insights further, data scientist Dr Harmony Liu consolidated solar radiation readings across Pasco, Touchet, Underwood, & Richland. As you can see, there's a precipitous drop in both solar radiation & air temp - showing this as a systemic issue for growers across Eastern WA since smoke rolled out on September 6:

And when we look at our Smart Orchard pilot, it's clear that Photosynthetically active radiation, often abbreviated (PAR), expectedly drops dramatically on September 6.

PAR designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to be so energetic that they can be damaging to cells and tissues, but are mostly filtered out by the ozone layer in the stratosphere. Photons at longer wavelengths do not carry enough energy to allow photosynthesis to take place.