I have some pink spawn which was being expanded out in jars of rye berries and popcorn kernels. There's been good growth and since a couple weeks ago the jar appeared to be completely colonized (at which time I left one jar sitting and moved another jar to a couple fruiting bags). It's been sitting on the basement floor since then, but I've noticed some pink coloration that seems to have gone throughout the jar, and there seems to be a bit of the pink also in the fruiting bags.

I prepared some jars of blue oyster spawn at the same time, using the same batch of rye and popcorn, and those jars are still snow white. This has me wondering, could I have possibly gotten contamination ONLY in the pink oyster jars while all of the blue oyster jars somehow escaped contamination? Or is this pink color natural for pink oysters? It just seems like an awful big coincidence that only the pink oysters would get contaminated when everything was prepped together in the still-air box and there was definitely cross-exposure between the jars.

Since this is my first batch of oysters I'm just not sure what I should be expecting.

Every summer in my neighborhood, this one tree will fruit a silky rosegill and we have standing permission from the homeowner to harvest it. This year, looks like there are two. I wish I'd passed by the tree earlier this week before the big one started to shrivel.

doi: https://dx.doi.org/10.3389/fbioe.2023.1229693

Teliospore 1000x Magnified in Phase Contrast

Yesterday evening I made this nice picture in phase contrast of a teliospore of Gymnosporangium clavariiforme I found and posted earlier. Measures roughly 85 x 14 µm. Quite proud of it, since this is one of the first usable images I got with the new microscope 😉

#microscopy #nature #mycology #fungi #biology #microscope #photography #mushroom #image #picture @mycology

MEA with yeast extract at 1g/500mL, 9 days of growth

Glad the fungal folks are finally migrating here from reddit :) Can't wait to have a thriving mycelial community round these parts 🍄

At the suggestion of another member I tried expanding my spawn on popcorn kernels. This involved boiling for about 20 minutes, drying, then pressure-canning for 90 minutes at 15psi. After cooling my spawn was divided between the jars, which were allowed to grow for a little over two weeks. On Monday I transferred the contents of a couple jars to fruiting bags with pasteurized straw and started seeing growth by the next day. I thought all was well.

On Wednesday, I started noticing some green stems. As I've been watching, this is actually growth from the popcorn kernels, and it's happening in all four bags! Now I'm quite frankly amazed that the cheapest generic popcorn from the store even has the capability to sprout, but after I put it through all that cooking I would have assumed it simply wasn't possible. I also wonder why it didn't start trying to grow in the original jar, and why it waited until it was in the bags?

So is there anything I should do about this? It will probably be at least another couple weeks before the mycelium is grown out enough to open some air holes for fruiting and I'm worried the corn will be trying to create its own holes before then, but maybe the bag is tougher than it looks. Anyway, any suggestions other than letting it go and waiting to see what happens?

tl;dr: Spawn grown on popcorn kernels, now popcorn is sprouting despite extensive cooking.

[Update] It's NOT the popcorn, there were other seeds in the straw!

TL;DR: both clusters are the same, but I will redo the test

Good morning, my fellow mushroom enthusiasts!

In my Original Post I examined the effects of additional nitrogen supplementation by using diesel exhaust fluid (urea) for growing mushrooms.

As written there, I had to update the post just a few hours after publishing it, since the buckets already formed pins after just 16 days!

Now, a few days later, I got my first harvest. 800 grams total, but (sadly) both buckets (sample and reference) looked the exact same. Even the mass was, almost by gram, the same.

What now?

At first, wait for further flushes. Maybe, the urea bucket will provide more than the reference.

Also, I will redo the test. This time, with WAY more urea. I've read somewhere, that many growers aim to have 1% nitrogen in their substrate by using husks.

In my case, this means 45 g AdBlue (15 g urea) per bucket. Also, I'll use less grain spawn next time for not altering the results.

... So, I've got some work to do! :D

I've lost track now of how long since I started on this, but I think it's been 2-3 weeks since I transferred my original spawn to grain jars? All of the jars have been fully colonized except for one jar of pink oysters, which fought against some kind of contamination but seems to have gotten going again. It had some good looking growth though, so I decided to use that jar plus one jar of blue oysters (but grown on popcorn kernels) for my first attempt at fruiting. If it is too weak and fails, well if was worth a shot and I wouldn't have gotten anything else from it anyway.

I'm using some 8" fruiting bags from ebay, and pasteurized chopped straw in a lime water bath overnight then let it drain today for about 2.5 hours. Each quart jar of spawn was split between two fruiting bags.

Now here comes the scary part... I didn't have room inside to work on this, and knew working with the straw was going to be very messy, so I set up a table in the yard. I wiped everything down with 91% ISO as I went, but being outside has me worried about the chances of contam. Guess we'll see?

So now I have four stuffed fruiting bags hanging out in the garage where it will be a little warmer than the basement. I had considered putting the bags in my garden but I'm worried about squirrels and such getting into them (especially when they start to fruit) so I figured the garage was safer. I'm expecting another 2-3 weeks of expansion before they're ready to fruit, but it's just a game of wait&see now. And assuming I get some mushrooms from this batch, I can bring it back full-circle and start a new batch of spawn (this time directly in the grain jars) from what grows.

One question I have for everyone... I have three more jars of spawn that are pretty well completely grown in (one popcorn and two rye berries). Should I put these in the refrigerator until I'm ready to transfer them to fruiting bags? I'm not sure how long they can survive at room temperature but I seem to recall they can hang out in the fridge for 3-4 months without any problem?

Last week I was checking on one of my compost bins and noticed that there was a group of these mushrooms growing on a clump of composting leaves. Given the heat, I'm surprised to see them growing in the bin. Any help identifying them is most appreciated.

Shot of under side

Saw this at the base of a 300 year old oak.

Little smaller than my hand.

TL;DR: Urea is a great supplement for substrates and culture media!

Background:

Fungi, need , next to an energy source (e.g. wood), nitrogen to grow. If too little nitrogen is available, growth suffers, which increases the risk of contamination, and yields also decrease.

Some species of fungi, including oyster mushrooms, turn into carnivores under these circumstances and secrete a secretion that attracts flies, which are then digested by it, along with their larvae.

Unfortunately, this is sometimes not only disgusting, but also introduces a lot of contamination.

Therefore, many growers use supplemented substrate, for example HWFT with grain- or soy hulls. This supplementation increases the nutrient content, but also the risk of contamination, which is why it must always be handled sterilely and be autoclaved. However, many growers do not have the capacity or want to do this.

For agar and liquid media, yeast extract or peptone is often used. Yeast extract colours the solution strongly, and peptone is somewhat expensive and difficult to obtain.

This is where AdBlue comes in. This is normally used for diesel vehicles to prevent the formation of harmful exhaust gases. AdBlue is a pure 33% urea solution, available at any petrol station for 2€/ litre. Urea is a very bioavailable source of nitrogen, which why it is also used in agriculture as a fertiliser. You know where I want to go....

Set-up of my experiment:

Agar medium:

• 4 plates with different urea concentrations were prepared. 0 g/l (reference), 0.25 g/l, 0.5 g/l and 1 g/l.
• base recipe: 40 g/l rice syrup, 17 g/l agar, 1l tap water (addition: the amount of rice syrup was too much back then, I halved it now for future recipes)
• the plates were inoculated with oyster mushroom culture (same size agar transfer of a fresh clone)
• the plates were regularly checked and photographed
• and then I compared the growth (appearance and size of the mycelium).

Substrate:

25 g gypsum, 2.5g urea and 2l water were added to 1 kg dry matter (hardwood fuel pellets).

The reference was identical, only without the addition of urea.

Approx. 500g of Grainspawn was added to the bucket (total content: approx. 3kg) and this was stored warm for growing.

Results:

Agar (after one week):

Imgur, 1 week

• Reference: little visible growth, mycelium looks very weak. Very fine, almost invisible hairs over the petri dish.
• 0.25 g/l: best growth. Very fast and dense
• 0.5 g/l: similar to 0.25 g/l
• 1 g/l: very strong/dense mycelium (almost rhizomorph), but slow growth.

After 2.5 weeks:

Imgur, 18 days

As after one week, only stronger (reference is now very overgrown with air mycelium, 0.25 looks best, 0.5 similar, 1 g/l little growth).

Substrate:

Bucket is almost completely overgrown after only a few days Imgur, 3 days; after one week completely. Imgur, 3 days/1 week

After 2 weeks it became a solid white block. Normally this takes almost a month for me!

Update, after only 16 (!) days:

The first pins were already forming just a few hours after posting! Imgur, bucket after 16 days No visible primordia on the reference bucket without urea...

Yield:

I will post/edit as an update later.

Normally it takes about a month for the first pins to appear for me. With the supplemented buckets it seems to take a bit longer so far. It didn't quite look like primordia were appearing yet.

The reference is already forming the first spots, which indicate that fruiting is imminent.

Further thoughts:

• Urea has an effect on growth
• I will use it in the future in my agar media and LCs at 0.3 g/l (1ml per liter)
• Effect on substrate and yield is TBD