Why do some tree stumps have hearts on them?

[Titi]

I've been cutting down trees in my town and I noticed that some tree stumps have the shape of a heart in the middle, while others have a circle.
If I'm not mistaken however they were all peach trees.
Does anyone know why that is?

 

[Ami Mercury]

Some stumps have special designs.

 

[1980 Something Spaceguy]

When you cut down trees, they can have special patterns on them.

 

[sn0wxyuki]

Is a special stump =) Fruit/non fruit tree create heart, butterfly, zelda, ginko, citrus and X and pine tree create flower, clover, music and star =x I might miss some can't really remember all xD

 

[dizzy bone]

Mushrooms grow around special stumps

 

[budewarmin]

Those trees are in love

 

[Rendra]

Here are the specail designs:
Pine Tree Stumps
Animal Crossing logo (leaf)
Cat face
Clover (very rare)
Flower
Musical Note (very rare)
Star
Other trees (but not beach trees)
Butterfly
Citrus fruit cross-section
Ginko Leaf (Crazy Redd's Logo)
Heart
Triforce
X

Mushrooms will grow around tree stumps with special designs (in town only)

When you cut down a tree with a regular axe or gold axe it is random if you will get a special designs or not, but using a silver axe (sold on island only--rare) gives you 100% chance of getting a special design.
The regular axe & silver axe will at some point break (gold axe never breaks). So if you are wanting special design tree stumps, use a regular or gold axe for the first 2 hits on the tree and then use the silver axe for the final hit. You will get a special design tree stump and your silver axe will last 3x as long.
I have also heard people say (I haven't tried it out myself) that if you open your town gate (local) before you start, if you don't get the special design you want, flip the wi-fi switch and everything will go back the way it was before you opened the gate. If you do get the design you want, then Save & Continue.
Good Luck.