30 CIRCULAR 912, U. S. DEPARTMENT OF AGRICULTURE 



is shrubby in growth habit and develops a crown spread approximately 

 equal to its height. The species suckers profusely under cultivation. 

 It appears to be a desirable species for erosion control and wildlife- 

 cover purposes. 



Juglans cinerea. — This species has been planted to a very limited 

 extent in the area. Trees were killed back in varying degree each year, 

 primarily as a result of insufficient moisture. In the test block sur- 

 vival dropped to 11 percent by the time the trees were 15 years old. 

 The species is not recommended for planting in the area. 



Juglans mandshurica. — This species was tested at the Mandan 

 station only. The trees suffered severe winter killing each year. The 

 species is not recommended for planting in the area. 



Juglans nigra. — This species was tested throughout the area. Kill- 

 ing back and losses were heavy in dry-land plantings during the 

 severe drought 3~ears of 1934 and 1936. The species is difficult to 

 transplant. It has no value as a dry-land windbreak tree but is 

 suitable for windbreaks under irrigation. A light crop of nuts was 

 produced most years in the Mandan test block. 



Juniperus communis. — This species, native to the area, has been 

 used extensively for ornamental purposes. It is frequently found 

 growing in the shade of other species. When planted in the open the 

 foliage is subject to "burning*' during the winter months. This 

 burning was responsible for the loss in the test block. The species 

 has no value for windbreak purposes but is a desirable ornamental. 

 It is quite drought-resistant and can develop considerable spread. 



Juniperus monosperma. — This species, native to the Wyoming sec- 

 tion of the northern Great Plains, killed back repeatedly. It is 

 recommended only for its native habitat. 



Juniperus scopulorum} — This species, native to the western two- 

 thirds of the northern Great Plains, is hardy except for the "burning*' 

 of foliage on trees exposed to northwest winds during the winter. It is 

 highly recommended for dry-land windbreak and ornamental planting 

 in the area. Among conifers, J. scopulorum is one of the easiest to 

 establish. 



Juniperus lirginiana.*— This species is native to the eastern edge 

 of the area and has been planted fairly extensively in windbreaks. It 

 is quite hardy and is highly recommended for both windbreak and 

 ornamental plantings (fig. 4). The foliage occasionally suffers from 

 "burning" during the winter. The species transplants fairly readily. 



Larix decidua. — Testing of this species was confined to the Mandan 

 station. It did well until the drought of 1934, when survival dropped 

 to 4 percent. The species is not recommended for dry-land planting 

 but is believed to be suitable for planting under irrigation. 



Larix laricina. — Testing of this species was confined to the Mandan 

 station. The behavior of the trees was similar to that of L. decidua. 

 It can be recommended for planting under irrigation only. 



Larix sibirica. — Testing of this species was confined to the Mandan 

 station, where it was free of winter injury. It is recommended for 

 dry-land and irrigated windbreak planting in the area. 



4 This species is an alternate host of cedar rust of apples, a disease injurious to 

 apple trees. 



