Can anyone verify C. tetrameria seedlings that I'm growing?

[viDda]

Hi Everyone.  I think I got some C. tetrameria seeds and have been growing them out to use as rootstock for dwarfing white sapote.  I also want to graft some yellow sapote #6 & #7 so I can grow it out for fruit.  Can you look at these and tell me if they look to be C. tetrameria?  I know the underside of the leaves get fuzzy.  Mine, perhaps because they are too young, still don't seem to be fuzzy.  The leaf color is a darker green compared to the white sapote seedlings I have.  I never heard of yellow sapote (C. Tetrameria) until I read Jack, Nipomo's post about dwarfing white sapote so my knowledge of them is very limited.  When I ask people about yellow sapote in South Florida everyone thinks I'm talking Canistel.  Even very knowledgable nurseries people here. 

[sc4001992]

nop, don't see any fuz on bottom side of leaf, it's a white sapote seedling.

[Jack, Nipomo]

Sure looks like C. edulis.  The fuzz on a C. tetrameria is very apparent, even so C. edulis "Suebelle" has some fuzz on the leaf underside.  Sometimes called "wooly leaf" sapote due to the very apparent "wool". My mature tetrameria trees on tetrameria rootstock (#6 and #7) are small like a peach tree.  The several mature edulis trees on edulis r/s are giants with corresponding base and height.  One trunk base is over 26 in diameter and 35 ft tall.  That tree has several grafts done years ago.  A Vernon edulis grafted on tetrameria R/S  that is over 20 years old is less than 6 ft tall.  The seeds on tetrameria fruit are roundish and much smaller than edulis (1/3 to 1/2) even on same sized fruit.  Many edulis and tetrameria fruits have a yellowish interior, all tetrameria (here) are yellowish.  Most edulis have white interior (here).  Flavor is distinctively different between the two.  #6 and #7 tetrameria were selected by CA CRFG group as having best flavor.

[Bush2Beach]

It may be that a more common name is Wooly Sapote or Wooly Leafed Sapote.
That does not look fuzzy enough to be Tetrameria to me. There are nuff hybrids with medium fuzz.

[Jack, Nipomo]

Vernon C. edulis white sapote leaf, #7 C. tetrameria leaf showing wooly or fuzzy underside.  It is most noticable when feeling the fuzz with fingers.  Light reflection is limited on the fuzz (wool)  These are not the only differences with these trees, also growth habit (size at maturity), seed characteristics and fruit flavor (not fruit interior color).  Then there are possible hybrids like Suebelle white sapote with fuzzy leaf underside.

[viDda]

Thanks everybody.  I was hoping the fuzz would come out later and wasn't showing yet because they are young.  They look different than all the other white sapote seedlings I have.  The white sapotes are of different variety seeds too.

[sc4001992]

Well you might be half correct. I took some photos today of my grafted c. tetrameria (wooly leaf) and noticed the young new leaves of the branch don't show much fuz but the older leaves on the same branch have the fuz. I don't have any seedling wooly leaf plants growing right now so I can't confirm if you are correct about the young leaves.