@Dave, please change the Dahlia custom data fields as follows.
Add these data fields, at the top, with a write box.
Year Introduced
Hybridizer or Originator
Edit the existing data fields as below adding
Orchette (OT) as a new form, and
Single (S): over 2 inches in diameter as a new size.
Form
Anemone-flowered (AN)
Ball (BA)
Straight Cactus (C)
Collarette (CO)
Formal Decorative (FD)
Incurved Cactus (IC)
Informal Decorative (ID)
Laciniated (V)
Miniature Ball (MB)
Mignon Single (MS)
Novelty (N)
Novelty Open (NO)
Novelty Fully Double (NX)
Orchid-flowering (O)
Orchette (OT)
Pompon (P)
Peony-flowering (PE)
Single (S)
Semi-Cactus (SC)
Stellar (ST)
Water Lily (WL)
Color
Bicolor (BI)
Bronze (BR)
Dark Blend (DB)
Dark Pink (DP
Dark Red (DR)
Flame Blend (FL)
Lavender (L)
Light Blend (LB)
Orange (OR)
Pink (PK)
Purple (PR)
Red (R)
Variegated (V)
White (W)
Yellow (Y)
Size
Giant (AA): over 10 inches in diameter.
Large (A): over 8 to 10 inches in diameter.
Medium (B): over 6 to 8 inches in diameter.
Small (BB): over 4 to 6 inches in diameter.
Miniature (M): up to 4 inches in diameter.
Ball (BA): over 3.5 inches in diameter.
Miniature Ball (MB): over 2 to 3.5 in. in dia.
Pompon (P): up to 2 inches in diameter.
Mignon Single (MS): up to 2 inches in diameter
Single (S): over 2 inches in diameter