There are two reasons why you would want to make a mushroom spore print. One is to help you identify a mushroom, and the other is to save mushroom spores for future cultivation.
In this post, we will cover all the basics of spore prints for cultivation: from making to storing, to germinating.
In a few days, we will post an article about creating and using spore prints for mushroom identification.
Ready to become a master spore printmaker? Let’s dive into it!
What Is a Mushroom Spore Print?
Spore prints are powdery deposits that you get when you allow spores to fall from a mushroom onto a surface, like a piece of paper.
These spores are the DNA carrier of mushrooms, so think of them as like the seeds of a plant, or the sperm of an animal.
Spores usually grow under the caps of mushrooms, in what are called the gills. Fully grown mushrooms have thousands of spores on just one gill. The color of spores can range from white to many different shades, including black.
Spore prints are living records of mushrooms created by carefully collecting, preserving, and protecting these mushroom spores for cultivation or identification.
How to Make a Mushroom Spore Print
It’s actually quite easy to make a spore print. You can make spore prints of mushrooms that you find in the wild. You can also make them from mushrooms that you buy at the grocery store or farmer’s market.
But there are some steps you need to take first, to ensure success.
Preparing to Make Your Spore Print
The mushroom that you wish to make the spore print with must be mature, since young mushrooms may not have gills and mature spores yet.
If you find a mushroom that you wish to make a spore print with, the best way to carry it home is to wrap it in wax paper. This will protect the mushroom without disturbing the gills. Other materials like plastic or cling wrap trap moisture too easily and may invite unwanted contaminations like mold.
As a rule of thumb when working with mushrooms, you should try to keep things as sterile and safe as possible. So, before you start your spore print, make sure that you wipe down and sterilize all surfaces in your work area with 70% isopropyl alcohol. Also, wear powder-free gloves while you work. This will decrease the chance of contamination with unwanted spores, microbes, and bacteria.
Making Your Spore Print
Spore Prints From Mushroom with Gills
- For mushrooms with gills, the spores are on the surface of the gills. To collect spores from your freshly picked mushroom, cut off the stalk at the highest point that you can without touching the gills. Use a sterilized tool, such as a scalpel or a very sharp knife. Then lay the mushroom cap — gill side down — on an index card, or a piece of aluminum foil, white paper, or glass.
- If you want to keep the stem intact while making a print, cut a hole in an index card, put the card on a cup. Then slide the stem of your mushroom through the hole until the underside is resting on the index card.
- To help the mushroom release its spores, put a drop of water on top of the cap. Don’t overdo it!
- Cover your mushroom with a glass or container as this will keep your mushroom from drying out while eliminating airflow. It will also ensure cleaner and less contaminated spore print. To keep the printing process dry, you can put in DampRid crystals to suck up any excess moisture.
- Depending on the freshness of the mushroom and the humidity of the enclosed area, your mushroom should release millions of spores onto the paper in 4 to 8 hours. You can leave your mushroom alone for up to 24 hours to ensure that enough spores have fallen.
- You now have your very own spore print!
Making a Spore Print from A Mushroom with No Gills
Not all mushrooms have gills. Some have pores instead. Such mushrooms are known as polypore mushrooms, and they usually grow on trees or logs.
Polypores can be tricky to make spore prints from. Some softer ones like the bolete, which is soft and fresh, will release the spores that are inside the pores underneath its cap quite easily.
Hard polypores take longer to mature before producing their spores, and they don’t let go of them easily. To encourage the harder polypores to release their spores, try wrapping them overnight in wet paper towels or newspapers before placing them down onto your preferred surface. Remember that the spore-bearing surface always faces downwards as it grows!
Some mushrooms, like puffballs, have their spore-bearing surface on the INSIDE. So, you may need to cut the mushroom in half to expose the spores before placing them onto the print surface.
Speaking of surfaces, you can use either white paper, aluminum, or glass as the surface on which you collect your spores. For cultivation and storage purposes, aluminum foil tends to be a favorite among mushroom growers as the spores will not easily stick to the surface of the foil.
If you’re planning on looking at the spores under a microscope, you should use glass or a microscope slide as it’s the best surface to allow observation without risk of contamination. And use a glass coverslip to protect the spores. Remember to wash the glass surface with soapy water, dry it with a wipe, and clean it
If you see any moisture droplets on the surface of the aluminum or glass that you are using, you should continue to let the spore print dry out in an enclosed covering again until all moisture has been evaporated.
Storing Your Mushroom Spore Print
Once the spore prints are dry and any moisture droplets have evaporated, put the print in a zip lock bag using sterilized tweezers. Store the bag in a dark, cool, and dry place like a closet or a drawer. If stored properly, the spores will be usable for many years to come.
The spores will stay in this dormant state until you decide to introduce nutrients to them in the future. At that time, they will come alive once again and will generate mycelium.
Germinating Your Mushroom Spores
What You Need
When you are ready to germinate one of the spore prints that you have stored, you will need the following materials:
- A sterile, flat surface: You can use a petri dish, a glass slide, or a piece of aluminum foil for this purpose. The surface should be clean and free of any contaminants.
- A sterilized tool: You can use a sterilized needle or scalpel to transfer the spores from the spore print to the sterile surface.
- Nutrient solution: You will need to add a small amount of nutrient solution to the spore print to help the spores germinate. Agar will work nicely for this.
Germinating Your Spores
Here are the steps to germinate a spore print:
- Place the spore print on a flat, sterile surface.
- Using a sterilized tool, carefully scrape the spores from the spore print and transfer them to the sterile surface.
- Add a small amount of nutrient solution to the spores. If you’re using a petri dish with agar, streak the tip of your sterilized tool into an “S” pattern across the surface of the petri dish.
- Cover the spores with a piece of clear plastic or a lid to create a humid environment.
- Place the spores in a warm, dark location where they can germinate.
- Check on the spores daily to make sure they are moist and not drying out.
- If you used agar and a petri dish, it is expected that your spores will germinate within a time frame of 5 to 15 days.
- Once the spores have germinated and grown into mycelium, you can transfer them to a suitable substrate, such as sterilized soil or a mixture of water and nutrients, to continue growing.
- If you wish, the germinated spores can be transferred to additional Petri dishes to form colonies.
It’s important to note that the process of germinating spores can be finicky and may take some time. It’s also important to follow sterile procedures to avoid contamination and ensure the success of your spore germination.
Wrapping It Up
So there you have it, All you need to know about making mushroom spore prints and saving your spores for cultivating new mushrooms.
Check out our article Mushroom “Seeds,” The First Step in Mushroom Farming to learn more about using spores to grow mushrooms. And if you’re up for a more advanced project, check out our article on Your Best Chance of Growing Morel Mushrooms Indoors.
And to see our video about making spore prints for cultivation, please click below.
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