So, while I was working on a certain other mod, I had an idea for a brief diversion: Silphium, Dwarven contraception.
The plant is loosely based off an herb of the same name that the Greeks harvested to extinction due to its supposed baby-blocking properties. Go ahead and add this to your plant_standard.txt file:
[PLANT:SILPHIUM]
[NAME:silphium][NAME_PLURAL:silphium][ADJ:silphium]
[USE_MATERIAL_TEMPLATE:STRUCTURAL:STRUCTURAL_PLANT_TEMPLATE]
[MATERIAL_VALUE:4]
[EDIBLE_VERMIN]
[EDIBLE_COOKED]
[BASIC_MAT:LOCAL_PLANT_MAT:STRUCTURAL]
[PICKED_TILE:231][PICKED_COLOR:2:0:1]
[SHRUB_COLOR:2:0:1]
[DEAD_SHRUB_COLOR:0:0:1]
[GROWDUR:425]
[WET][BIOME:ANY_TEMPERATE]
[USE_MATERIAL_TEMPLATE:DRINK:PLANT_ALCOHOL_TEMPLATE]
[STATE_NAME_ADJ:ALL_SOLID:frozen silphium draught]
[STATE_NAME_ADJ:LIQUID:silphium draught]
[STATE_NAME_ADJ:GAS:boiling silphium draught]
[MATERIAL_VALUE:4]
[DISPLAY_COLOR:3:0:1]
[EDIBLE_RAW]
[EDIBLE_COOKED]
[PREFIX:NONE]
[SYNDROME]
[SYN_NAME:sterile]
[SYN_AFFECTED_CLASS:GENERAL_POISON]
[SYN_INGESTED]
[CE_ADD_TAG:STERILE:START:0:PEAK:5:END:100000]
[CE_PHYS_ATT_CHANGE:DISEASE_RESISTANCE:115:0:START:0:PEAK:5:END:30000]
[CE_FLASH_TILE:TILE:231:2:0:1:FREQUENCY:4000:1000:START:0:END:100000]
[DRINK:LOCAL_PLANT_MAT:DRINK]
[SPRING][SUMMER]
[USE_MATERIAL_TEMPLATE:SEED:SEED_TEMPLATE]
[MATERIAL_VALUE:4]
[EDIBLE_VERMIN]
[EDIBLE_COOKED]
[SEED:silphium seed:silphium seeds:1:0:1:LOCAL_PLANT_MAT:SEED]
[FREQUENCY:20]
[CLUSTERSIZE:3]
[PREFSTRING:contraceptive properties]
EDIT: Sterile Dwarves will now flash Silphium's icon, so you can see who's not makin' babies. I also made it work for a whole season; easier to keep track of.Basically, what we have is an aboveground crop. It's inedible raw, but if you brew it, you'll get a booze that will make the dwarf sterile for about half a season. I also added in a bit of disease resistance, since Silphium was also valued as a bit of a cureall. The plant is pretty rare, and a bit hard to farm, but feel free to change that for your own game if you want it to be a little more easy to obtain.
Aside from generally stymieing the onslaught of disgusting, useless, tantrum-inducing dwarf larvae, there are a few interesting applications I can think of. Through clever use of burrows, and/or assigning the draughts to be carried by the military, you can carefully select who breeds in your fortress. For example, you can stop your female axelord from giving birth and wading into battle with a baby on her arm, or restrict breeding to an elite class of Dwarves (your starting seven, for example).
Let me know what you guys think!