Serophyttm . ....0000ecnaccneneeceenerces- 
Sesbania .. 2.2.2.2. eee se cee ee eee aee eee 
Setaria......... 
Seutera 
Seymeria 
Shag-bark hickory. .........2.---.-2s200- 
Shaweria .....--- 2-2 eee eee eee eee eeeee 
Shell-bark hickory. .....--.-------------+ 
Shepherd's purse 
Shittim wood ......-...-.------.-----2-6- 
Shooting-star 
Short-leaved pine 
Shrubby trefoil ..........-.2..-2..-2...4-. 
Sicyos 
eee eee emcee ae eee eee ee eee e eens 
eee ee ee ee ee 
Sidalcea.......ee cee eee cence ew ene c ee eweces 
Sieglingia..... wean ewer cacccsccnascacseaes 
Silene....----.----------- eee eee eee eee 
Silkweed ........--..----2 020+ +e eee ee eee 
Silky cornel...........-...0-222. 22 cs eeeee 
PANiC-Qrass ...-.-.. 222.2 ee eee eee ee 
Silphium......---...-.-2.- ee eee eee een e eee 
SIMARUBACEZ...... Sec ccee ewe een as casaces 
Stmesia 
Siphonoglossa. ...........2e0020- 2 eeeee eee 
Sisymbrium..........-.2....--2... 200200 
Sisyrinchium 
Sitanion 
SiuM .. 2. ee eee eee 
Six-weeks grama........ cece eeeeceeeenee 
mesqulit..... 2-2. ee see e eee enone 
Skulleap 
Sleepy catchfly 
QTASS........--------- 22-2 ee eee eee 
Slender crab-grass .........-. 
fescue .. 2... .e ee eee eee ee eee eee 
ee 
reed grass ....-...2--2- eee eeeeee 
spike grass .-....2..-eececeeeenee 
Slippery elm 
Smaller Solomon’s seal.........---+--+00- 
Smartweed..........-..-+--4-6 wecencaaes 
Smilaeind. .--.- ween ee ene eee eee eee ee eee ee 
Smilax 
Smut Srass ...0...---- seen wee eee eee neces 
Snake plant.......-...-----.-..----0-000- 
Snakeroot....... eee eee eee eee eee oaee 
Snapdragon.....-.---..--.----22--- eee ee 
Sneeze-weed .......22226 cece e ee eee eee -- 
Snowberry...-..sssees-e- + eee e eee ee eeee 
Soapberry.....-----.-.--.----2-00- eee eee 
Soapberry family .....-......----.. weccee 
SOLANACES . 2.2... sc eee eee e cece ee ween ee 
Solanum 
Solidago .-............---- cece ee enne aeeee 
Solomon’s seal ...........----------4- aes 
Sonchus 
SOPhora......cceee cence ee cece eneeeeenanee 
Sorghum......... aneeeee ence eee eeeweenee 
Sour-gum tree 
Southern canary grass..........---..---- 
Se ee rr 
DiMC. 2. eeeeeecccaccccnnnncace 
Page. 
402 Southern poverty grass ......-..222...055 
81 Sow thistle ................---.-2-.------ 
535 | Spanish bayonet -.......--..---.----..--- 
137 Need eS... see eee eee eee eee eee 
509 OAK . 22. aeseeeee sees eee eee enews 
269 | Spartina .......2...2. 2... eee eee eee eee 
313 | Spatter-dock 22.2.2... 22 eee eee eee eee 
410 | Spear grass ......-.020. 222 eee e eee eee 
323 | Spearmint .........22020. cece ee eee eee 
410 9 Specularia ...........22 020 cece eee eee eee 
20) Speedwell. .........c0. cece eee eee e eee ees 
257 | Spergularia ....-.2..-2-.....-.2.2---02--- 
255 Spermacoce ....--..0..---2 eee eee eee eee eee 
554 Spheeralcea .......... eee eee ee ee ee eee 
54. Spice bush... 2... ee... eee eee eee ee eee eee 
125 Spider bent grass ...........- te aececceces 
124 | Spiderwort ............-2.2.2- eee ee een eee 
39 | Spiderwort family 2.2.2.0... 0. cece ee cee 
37 | Spigelia.....2....2 2.0.22. eee ee eee eee 
587 | Spike-rush..........22------- eee ee eee ee 
29 | Spilanthes ............. 2.0200. s eee eee eee 
265 | Spindle tree.........2.2.2.-..2-2002-- eee 
150 | Spiny clotbur.....--..---.2.----.--.222-- 
502 Spirwa... ee. ee eee ee eee ee eee eee 
205 Spiranthes .. 2.2.0 ..000 0002 e eee eee ee 
55 | Spirodela ...............2..2---------2 00 
220 | Npirostachys ......22.--.0-..0022020222 20 
324 | Sporobolus............-.-...------22+--0- 
16 Spotted cowbane ......-.-..-+-.2-2--.---- 
428 medick ......-2.2--20--eeeeeee eee 
550 — Sprouting crab grass........---.--------+- 
146 Spruce pine...........---------.22------- 
149 | Spurge... 222. e eee eee ee eee eee ees 
532 nettle. ...cce cee ceeeceeeeeeeeeeeees 
533 | Spurge family..............--.220-- eee eee 
340 | Spurred butterfly pea........----------6- 
29 | Squaw-weed ..........c0. 222. e cece cee e eee 
516 | Squirrel tail............---.---.---2---26 
501 | St. Augustine grass. ...-...22. 2... eee eee 
547 | St. John’s-wort.............2-2...22-.2028 
517. “St. Jobn’s-wort family.......-.-....--..-- 
545 St. Peter’s-wort ..........2..202.222.2.2-22 
406 | Stachys ..-.....2-2.--------------------- 
438 | Staff-tree family.......... 0.2.20 0222-220--- 
377 | Standing Cypress ......--0-0e-- ween e renee 
438 | Star-Qrass ....-..-.cese see eee ee eee eee eee 
432 | Star-thistle.........2....2220. 22 eee 
518 | Starwort..-.---.-.---2-.--0-- eee ee ween 
321 | Statice .. 2.22... eee eee ee eee ee eee ee 
145 | Steironema.....-..----.------------------ 
306 | Stellaria ......-.-...--------------------- 
931  Stemodia.........2... 2-20-2222 222 e eee ee 
156 | Stenandrium............-----..--------4- 
66 | Stenorrhynchus .....-....---------------- 
64 | Stenosiphon.........------2e--eeeee eee 
296 | Stenotaphrum ......2..2..2...e sence eee . 
297 | Stephanomeria ......-...---. ------------ 
188 STERCULIACEAE .. 21sec eee econ eee een eee 
438 | Stevia......---.-- eee ee eee e ee ene eee wee eee 
250 | Stevia .....ccceceeeenee enenenececce a caceee 
72 | Stickseed ....... 20... seen cece eee eee one 
494 | Stick-tight....- we eee ee reece eenenr eens -- 
151 | Stillingia ...-.....0.-..-eee eee e eee eeeeee 
512 | Stipa .-.-. eee cee eee eee eee eee ee 
554 | Stipa ........... eee eee ee cece ween 493, 
525 
443 
426, 429 
244 
29, 194 
254 
285 
223 
404 
515 
