As the growing season comes to a close every autumn, something magical happens in the forest which has massive implications for the lives of billions of creatures.
They’re called mast trees! And today I’m going to share a quick introduction with all the basics you need to know to identify mast trees and reap the benefits of their harvest. So what are mast trees?
A mast tree is any tree that produces major crops of food for wildlife or human foragers by virtue of periodic booms in seed production.
One great example is oak trees, which in some years produce a staggering quantity of highly nutritious nuts that can be stored by animals long into winter. While in other years they produce almost no acorns in comparison.
These periodic booms of nutrition in the forest have massive consequences for overall wildlife patterns, and create opportunities for the keen nature lover who wants to benefit from this temporary resource by harvesting wild food.
Here are some unique things about mast harvests that make them so valuable and interesting:
- Many mast foods have great storage value, avoiding rot, or freezing on the trees to provide quality food even when everything is dormant.
- High nutrition content, especially fatty nuts, helps mammals build up fat stores for winter.
- Periodic booms of mast production trigger a cascade of ecological effects that affects mammals, birds, insects & even diseases like lymes.
Benefits of Learning Your Local Mast Trees
- Great foraging: These trees produce massive food larders on a periodic basis (typically once every 2-8 years). If you know how to identify a mast year, you can benefit from these special harvests.
- Common: Mast trees also happen to be extremely common so it’s very likely that you already have mast trees growing near you, which makes them very accessible to study, even in city environments.
- They teach us to see connections: The real magic of mast trees is that they’re so deeply connected to everything else in the ecosystem. Understanding these connections is a big key to tracking and finding wild animals, while gaining a deep appreciation for the delicate balance of nature in your local area.
Imagine learning just ONE tree that provides food and also teaches you about birds, animals, insects, weather & seasonal influences and so much more, all in one swoop!
So what are these amazing trees that already live in your backyard?
7 Common Types of Mast Trees
It’s important to realize the classification of “mast trees” is not a taxonomic or genetic category. It’s really more of a qualitative description that identifies any tree which generates periodic larders and lacks in seed production.
There are dozens of different types of mast trees growing in almost every environment, but some species are much more common and prolific than others.
So here are some common mast trees you might already be familiar with.
1. Oak Trees
You probably already know that Oak trees produce acorns.
You might even be aware that these incredible nut harvests are edible.
But have you ever noticed how some years the ground is covered with acorns, while other years it seems like there’s almost none? That’s because Oaks tend to have very extreme masting cycles.
If you’re interested in viewing wildlife, or harvesting wild foods for your own use, these oak mast cycles are incredibly to understand because they have such dramatic differences in nut production from year to year.
On a good year for acorns, pretty much every animal in the forest will be gathering around the oak forests, and their populations will be increasing. On a bad year, they’re forced to disperse and find other means of survival.
Acorns are a massive source of food for deer, pigs, squirrels, jays, woodpeckers and many more animals.
So if you want to find wild animals in autumn, it’s essential to answer the following two questions:
- Are the oaks having a mast year?
- Where are the dominant oak forests in your local area?
Go sit in a highly productive oak forest through the fall and you’ll be amazed to witness all the diversity of insects, birds & animals who depend on those acorns for survival.
Most oak trees take a minimum of two years, and as many as 4 years to produce a bumper crop.
2. Apple Trees
Animals will travel from far and wide to reap the benefits of a fruiting apple tree… deer, raccoons, foxes, coyotes, squirrels, and pretty much every other herbivore and omnivore.
Orchards manage apple tree masting by pruning branches in specific patterns to promote more stable yearly production, but apple trees growing wild or unmanaged will tend to produce bumper crops every 2 years.
Even after the fruit drops there are insects, birds & wasps who come to feed on the fruit too.
Then all these gathering and concentrating wildlife patterns creates opportunities for the carnivores as well, like hawks, weasels & wild cats.
The best way to truly appreciate all these deep connections is to have a sit spot beneath an apple tree where you can observe the changing wildlife patterns from winter into spring, to summer, and into fall.
3. Spruce Trees
At the end of summer, the spruce cones ripen and inside each little cone hole is a tiny seed packing a pretty big punch of calorie dense protein & fat.
Because the seeds are so small, mast from spruce trees tends to not be used by human foragers, but it provides tons of food for smaller animals like squirrels, mice & birds.
Pay attention to how wildlife patterns change around spruce trees at the end of summer. Pay attention and notice that spruce trees don’t produce major harvests every year.
The greatest changes in wildlife behavior around spruce trees will always occur during a mast year, so it’s important to identify and discern how many flowers and cones are developing from year to year.
4. Eastern Redcedar
As I mentioned in another article on coniferous tree identification, the eastern red cedar is actually in the Juniper family, so they produce bitter little blue medicinal berries that are enjoyed by cedar waxwings.
Juniper berries stay on the tree for an incredibly long time, even years before they’re finally ready to harvest. These small blue berries pack an incredible medicinal punch.
Pay attention to the relationship between berry-loving birds and cedar trees. How does the berry production change from year to year? When do the birds gather and eat these?
If you can beat the squirrels, deer, chipmunks & birds who also love these nuts, hazelnuts are an incredibly rewarding harvest because the trees are so incredibly productive.
This is the same nut used to make the popular food snack nutella.
Keep an eye out for the tiny hot pink flowers, and long yellow catkins in early spring. Then watch as the flowers fade and become replaced by little nuts forming on the branches.
Stay alert in August/September as the nuts ripen up and you’ll see some dramatic appearances of forest creatures coming in to eat them!
An interesting fact about walnut trees is they have allelopathic qualities which means they exude a chemical into the soil which inhibits other plants from growing and stealing their access to nutrients.
On average – walnut trees produce 571 walnuts per tree, and can produce yields up to 974 walnuts on a single tree.
That’s a very significant amount of food when you consider that walnuts are pretty big!
Another important feature of walnuts is their thick outer flesh which protects the edible part from many animals. Squirrels can still get into them pretty effectively, but deer and other herbivores have a much harder time.
It takes a bit of processing to access the nuts, but the rewards of walnuts are tremendous.
Beech nuts are small, but can be a good food source in mast years if you live in a place with lots of productive trees.
It’s important to watch the trees carefully as the nuts ripen because this will help you identify whether there’s a bumper crop coming.
Beech trees are susceptible to beech bark disease, which interestingly, can cause beeches to produce more frequent bumper crops.
Why Do Mast Trees Have Bumper Crops?
It’s generally thought that mast trees produce bumper crops in order to minimize seed predation by animals like mice, squirrels, deer, pigs, etc.
By periodically starving the animals in non-mast years, and then suddenly overloading the landscape with an overabundance of seed, trees maximize the number of seeds that get to germinate.
This is why trees will go 1-7 years producing a greatly reduced amount of seeds, and instead focus on their own growth & development. Researchers have even measured tree growth to show that trees grow at an increased rate during non-mast years.
The actual mechanism behind how trees synchronize these mast years is still being studied, but it likely has to do at least in part with grand scale temperature changes from year-to-year.
How Do Mast Trees Affect Animals?
Mast production is one of the key ecological drivers behind dramatic fluctuations in wildlife populations like mice, deer & squirrels.
In bust years, animal populations shrink, starting with the herbivores, and then moving up the food chain to carnivores over a period of months and years.
Then in mast years, animals are suddenly inundated with more food than they can possibly consume and store, causing their populations to boom and again revitalizing the entire food chain.
This is why some years it seems like there are so many more squirrels than other years. It’s because the excess food triggers an increase in breeding and mating habits (Click here if you want to learn about the complex mating habits of squirrels!)
These booms in seed-eating animal populations then extends to the predators like hawks, owls, foxes & wild cats. It even affects populations of parasites like ticks that feed on those animals and have the ability to spread diseases to humans!
So as you can see, mast production sets off a cascade of effects throughout an entire ecosystem that affects basically every animal in the environment, even including human health & wellbeing.
Observe Mast Cycles To Increase Your Knowledge of Nature!
By being an astute observer of mast trees, you can learn to identify when these cycles are preparing to occur, even before they happen.
Mast knowledge makes you a much more intuitive reader of nature and tracker. And could even play an important role in your own survival strategy if you were ever trying to live off the land.
Here are 5 steps to build your awareness of masting events in your local forests:
- Learn which trees produce mast crops in your local forests
- Research their typical mast cycles so you know how often to expect bumper crops
- Practice watching the stages of growth to identify flowering, pollination, seed production & signs of ripening.
- Look for changes in wildlife behavior & population growth as a result of these masting events.
- Repeat each year for new insights and discoveries!
These 5 steps form one of the most valuable yet under-appreciated skills of tracking and watching wild animals.
How To Harvest From Mast Trees
The key to getting the best possible harvest from mast trees is to know ahead of time when trees are getting ready to produce a bumper crop. This way you can prepare ahead of time for the harvest.
There is great value in carefully observing trees through all 4 seasons so you can understand their progress in dormant, leafing, flowering & fruiting stages.
Taking full advantage of mast harvests requires preparation and planning.
You need to have a plan around how you’re going to collect the food, process it and store it.
Traditionally, harvesting from mast events in the forest would involve entire communities of people with some designated gatherers, others focusing on shelling the nuts, and others still watching over the curing & storing process.
This entire process can take several days or weeks to complete, but the end result is massive stores of food that will last for many months or even years.
Another technique is using mast harvests to fatten up domesticated animals like pigs before winter. This way the animals harvest for you and then you just need to process the meat.
With all of this in mind, remember to be conscious of the fact that mast forests produce these booms of food precisely in order to ensure the next generation of trees.
Always treat mast forests with respect so we can ensure they are able to continue thriving and supporting life for many thousands of years to come!
Tom Ahlberg says
My cedar trees seem to have produced the largest crop of seed that I have seen in 32 years. These are not small blue berries but very small brownish seeds that fall and clump together flogging gutters and making mats on the driveway and streets. Is this a mast crop?
Brian Mertins says
Yeah it sounds like a mast crop to me! The eastern redcedar described above is in a different family from true cedars.
True cedar trees will have the small brownish seeds like what you’re seeing. It’s not likely to be used by people because they’re so small but birds and small mammals probably still like them.
You can learn more about the different types of cedars in my other article on coniferous identification if you’re curious for more on that: https://nature-mentor.com/how-to-identify-coniferous-trees/