
What are you looking at? (And why do I keep having to ask that question at the beginning of my posts? It’s unnerving, even to me!)
This is an oak tree twig, with some tiny leaves and even some flowers, if you know what they look like. They’re not even showy–they’re like birch flowers–long strings of unremarkable chartreuse florets. And like birch flowers, they put out a remarkable amount of pollen too. So if you are sneezing, there’s probably a birch or oak tree nearby.
Every year I do a post like this because while Professor Doug Tallamy loves oaks because they feed so many pollinators, I love oaks because they herald the last frost. Once the oak leaves are the size of “little mouse’s ears” (and you can see that these leaves are significantly larger than that!), you have had your last frost!
I am not quite sure when I first heard this old-time farmer’s saying but it’s been decades now since I have been paying attention to it and the oak leaf saying has never failed me.
Now, am I going to go out and plant tomatoes and basil because the oaks have leafed out? Of course not! But when the TV forecasters are saying “cover your plants, there might be a frost tonight, ” I just look to the oaks. If they have leafed out, I don’t worry about a thing. I know that whatever is out there isn’t going to be harmed by frost because at least at my house there won’t be any frost.
The wonderful thing about these so-called farmer’s sayings is that they were developed for a reason. Long before we had “science” to tell us when to plant, we had to look to signs in nature. And in a sense, we are still doing that–it’s called phenology, which is the study of seasonal natural phenomena.
You may have heard of it a lot more in relation to climate studies–they are studying when trees are leafing out–if they are leafing out earlier, whether pollen and allergy seasons are lasting longer, how migration is being affected–things like that.
But before we had to worry so much, well, we still had to worry, because our forebears still didn’t want to plant too early and lose their precious crops. And that’s how the “oak leaves the size of little mouse’s ears” sayings–and others like them–came about.
So if you are in a cooler climate like mine, find an oak near your property to monitor and you’ll never wonder about your last frost date again. You’ll always know for sure by the timing of that oak’s leaves. Try it for yourself!