Table 4

The Effects of Shelterbelt-Planting on Livestock Production (2SLS)

Variableslog(No. of
Cattle/Acre)
(1)		log(No. of
Pigs/Acre)
(2)		log(No. of
Chickens/Acre)
(3)		log(Expenditure
on Feed)
(4)		log(Revenue
from Animal
Products/Pasture)
(5)
Proportion protected by shelterbelts*0.197−0.3180.05760.173
1945-1950(0.122)(0.196)(0.175)(0.211)
1954-19590.562*** (0.187)−0.137 (0.243)−0.0726 (0.270)0.573** (0.290)
1964-19690.854*** (0.249)−0.283 (0.346)0.588 (0.544)0.523 (0.537)0.655* (0.363)
1978-19820.855*** (0.294)−0.729* (0.440)1.190 (1.115)0.660 (0.595)0.725 (0.554)
1987-19921.004*** (0.352)−0.803 (0.522)0.987 (1.162)0.776 (0.646)0.783 (0.611)
Year and county dummiesYesYesYesYesYes
Outcome variables in 1910-1930YesYesYesYesYes
Other control variablesaYesYesYesYesYes
Erosion from the Dust BowlaYesYesYesYesYes
Proportion above the Ogallala
Aquifera		YesYesYesYesYes
Observations2,5742,5472,4001,6282,568
Number of counties234234234234234
R-squared0.7020.9720.9340.9020.940

  • note: Yield of corn in column 2 is missing for 1969 and 1974; yield of all hays in column 3 is missing for 1945; irrigated acreage in columns 4 is also missing for 1945 with its baseline year 1935 (1930 for other variables)

  • ↵a “Other control variables” include rainfall and temperature for each year and all the other variables listed in Table 1 from 1910–1930; “Erosion from the Dust Bowl” from Hornbeck (2012) include proportions of high- and medium-eroded as in Table 1; “Proportion above the Ogallala Aquifer” is from Hornbeck and Keskin (2014). All these variables are time invariant and all interacted with year-dummies. Standard errors clustered at county level in parentheses:

  • ↵*** p < 0.01

  • ↵** p < 0.05

  • ↵* p < 0.1