1910} HOWE—REFORESTATION OF SAND PLAINS I4I 
reproduces itself under the protection of the pitch pine, which is 
shown in the sample plot given on p. 140 (fig. 7). 
3. SUCCESSION POSSESSING THE SOD-FORMING STAGE.—Many of 
the cultivated fields on the sand plains were “seeded down,” bore 
crops of hay for a few years, and then were turned over to pasturage. 
fy ie C 
{ ¢ C1 
ce Cc ¢ Gicu_} 6 1} 66. 
4 U ¢ 
PELE cL tie ¢ a 
+ i 6 
Teseq g 
1S | | | ps es cic see fee Oo BRO Ines aM et 
Rg 
gee 7 8 ¥ 
ee : 
3 c 
on es 
}—+---4 PS 2: Cj 
RR at BS GIG 2 ae ee 
eB SES ES TE ¥ 
cu 
12h Waal ee & & cc 
Sam C 
2 ee os 
ae BS St 18 c 616 2 
4 c § 
EE ER Cl hd 
om Se ie c 3 
See & Gis Ch | jeu cu. 
cle e i 
ae £ § je ee 
See & 8\s 1g 
ry 6 PS. = 
bee 8 ct & Lod 
¢}] ic. i a ie 
| 8 § 
PS 3. 6 
a : i { 
FS a {ie ti al S2 
| i y 
Fic. 9.—Permanent sample plot 35. Forty-year-old stand of pitch a Col- 
chester plain, 4 meters square; PR, Pinus rigida 1; PS, Pinus Strobus 1 5 QV, 
velutina 2; QA, Q. alba; C, Carex pennsylvanica 56; G, Gaultheria paces 46; 
CU, Chimaphila umbellata 11;° GB, Gaylussacia baccata 2; D, Diervilla Lonicera 1; 
V, Vaccinium vacillans 1; B, Bock populifolia 1; A, Acer rubrum 1; R, Rubus alle- 
Sheniensis 2; S, Solidago ep 
Other fields formed a sod naturally without artificial seeding and 
were used as pastures. The chief sod-formers in this case were 
Poa pratensis and Danthonia spicata. After pastures formed in these 
two ways have been grazed for several years, they begin to lose their 
fertility. The first manifestation of this is the dying out of Poa 
pratensis, which is replaced by Danthonia. In course of time 
Danthonia gives way to Polytrichum commune. Most of the pastures 
