Pomes and Berries and Drupes, Oh My!

Fruit can be confusing. Everyone knows that tomatoes are fruits, but did you know that squash and cucumbers are too? Or that strawberries aren’t berries, but melons, lemons and cucumbers are? At first it might just seem like scientists are being picky, but there is some method to the madness.

There are two different classes of fruits: simple and fleshy. Simple fruits tend to be dry and include things like wheat, walnuts, coconuts and maple samaras. Most people are more familiar with fleshy fruits, so that’s what we’re going to focus on. Fleshy fruits are made from the ovary of a flower and are, like the name suggests, soft and squishy. There are many different types and the best known, and most misunderstood, is probably the berry.

“Berry” is a bit of a misnomer.  Many fruits with berry in the name are not technically berries, such as the strawberry or the raspberry. Botanically speaking, a berry is a simple fleshy fruit produced by a single ovary. Some examples are avocados, bananas, blueberries and grapes. There are two different kinds of modified berries, the hesperidium and the pepo. Hesperidia are citrus fruits with thick, bitter rinds and very juicy interiors such as lemons, limes, and kumquats. Pepos are melons, squashes, and cucumbers and have thick, leathery skin.

Raspberries (by Yongxinge via Wikimedia Commons)

So what are strawberries and raspberries if they’re not actually berries? Strawberries are accessory fruits. This means that they come from a part of the flower besides the ovary. In the case of strawberries, some of the fleshy part comes from the receptacle, just like figs and mulberries. Apples and pears are a specific type of accessory fruit called a pome and some of the flesh comes from the hypanthium. Raspberries are aggregate fruits. This means that they come from single flowers that have multiple carpels. These carpels form individual fruits which together make the aggregate. If you look closely at a raspberry, you can see that it’s made up of many parts.  

Another common type of fruit is the drupe. Drupes, also known as stone fruits, are composed of outer skin, flesh and a hard seed in the center. Like all simple fruits, they come from the ovary of a single flower and include mangos, olives, cherries and peaches. And finally, multiple fruits come from multiple flowers that produce many fruits that mature into a single, larger fruit, such pineapples, figs and mulberries.

It is important to note that many botanical terms are not mutually exclusive, which is why an apple is both a pome and an accessory fruit, and figs and mulberries are both accessory fruits and multiple fruits. I hope this encourages you to look at your fruits (and some of your “vegetables”) more closely! To learn more about the different parts of the flower that I mentioned about, click here.

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One thought on “Pomes and Berries and Drupes, Oh My!

  1. I like this the few other posts I’ve looked at (how to become a botanist, how not to apply to grad school) a lot. This one I like b/c it hints at some of the arbitrariness of botanical terminology. Perhaps you’ve seen Spjut’s monograph on fruit terminology from NYBG? Maybe arbitrariness is the wrong word,, and pickiness wd be better. Why is the fruit of Asteraceae a cypsela rather than an achene? b/c it’s derived from 2 gynoecial primordia, and that’s the name the Asteraceae folks gave it, i guess. Functionally is a cypsela really different from an achene? I don’t know, but am skeptical. Closer to my heart is why people call the fruits of apples and their kin apple fruits (pomes) when they could just as well call them berries? is the fruit of Vaccinium species w/ inferior ovaries any less hypanthial? lots of nice SEM+sectioned material-based papers on Rosaceae floral and fruit development, but not so many on Vaccinium, and definitely none comparable (i.e. using SEM or equivalent LM methods) as far as I’ve seen.

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