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Up the Malus and Pyrus and down the Prunus?

Malus and Pyrus is Dr M’s eXtreme botanical rhyming slang for “going upstairs” – up the the good old apples and pears! More of that later!

There is already hint of botanical logic in Dr M’s foolishness, it IS all about the good old Apples and Pears, (i.e. Malus and Pyrus).

Oh, plus one other fruit tree, the Cherry (Prunus).

So, three of your five a day into the bargain!

OK to start at the beginning, recently Dr M was asked by a devotee of Dr M Goes Wild:

“Can you tell me how to tell a pear or apple tree from a cherry tree at flowering time? Is it obvious?”

To which Dr M replied, nice question!

And, with all these blossoms still around us, an important botanical question how to tell your Malus and Pyrus from your Prunus!

So look at the images above, can you sort the apples from the pears, not to mention the cherries? Have a go!

The best check is to look at the flowers, and there’s nothing too tricky here, the floral differences separating apples and pears from cherries are quite clear, and only a tiny bit more subtle for separating apples from pears, read on!

All of these plants are in the Rose family, Rosaceae, but the basis of the separation is that  apples and pears are in a different sub-family to cherries.

And if they are in different sub-families then this is an eXtreme botanical clue that there must be something quite different about them!

Cherries (Prunus) are in sub-family Amygdaloideae (which includes cherries and plums) and apples (Malus) and pears (Pyrus) are in sub-family Maloideae (which includes a wide range of genera including apples but also Sorbus (Whitebeams), Cotoneaster and Mespilus (the Medlar).

Now, a key difference between the sub-families lies in the fruit; cherries (and plums) have drupes and apples and pears have pomes.

So what, exactly, are drupes and pomes?

Well, the cherry fruit that you eat is known technically as a drupe, a fruit with an outer fleshy part enclosing a hardened pit or stone with a seed (kernel) inside. So, if you cut open a cherry you will find one “seed” (with a very hard stone-like outer covering that you can break your teeth on!).

However, the fruits of apples and pears are known as pomes (no coincidence that apple is “pomme” in French, it’s yer Latin derivation innit!?). A pome is a fruit comprising one or more carpels surrounded by accessory tissue.

So, cut open an apple or a pear and of course you’ll find several seeds, though you might call them pips! But whatever you call them, apple and pear pips are quite different to cherry stones.

Despite what kids might say as they hand you back a massive, hardly nibbled apple core, it’s all edible, and Dr M is one of those distinguished group who will eat his apples and pears pips, core and all! He’s a little more careful with cherries!

The seeds are formed from the ovules which are enclosed within the carpels, so cherries have one seed and so just one carpel per flower while apples and pears have a number of seeds and several carpels (hint: count the stigmas and this equals the number of carpels).

Also, in cherries the flower has a superior ovary which means the sepals and petals are inserted down below the ovary, whereas in apples and pears the ovary is inferior and the sepals and petals are inserted up above the ovary.

So remember, UP the apples and pears (sepals/petals inserted above the ovary), DOWN the cherry (below the ovary) nice eh?!

Check the images of the  flower sections carefully, you should be able to spot cherry (flower C) from the superior ovary with single stigma and single carpel.

But the next question is how to tell your apples from your pears?

Apple flowers (A) often have petals which are pink flushed on white (though varieties with white or pink petals also occur), yellow anthers, with styles fused together below.

Pear flowers (B) have pure white petals (only rarely tinted yellow or pink), purple anthers, and free (unfused) styles.

Check the images of the  flower again, you should be able to separate apples and pears from the anther colour but also look for the styles – fused below in apple and unfused (free) in pear.

OK, that’s more than enough eXtreme botany for now, time fro Dr M to enjoy a bowl of Prunus and then head up the good old Malus and Pyrus for a well-deserved nap!

 

 

 

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