New Birch and Spruce

Last week I described two new varieties of American elm which have resistance to Dutch elm disease. This week I will share information about a new white birch and a new columnar spruce which should replace one of my most disliked evergreen, the arborvitae.

Parkland Pillar® Asian white birch is a selection of Dakota Pinnacle®, an introduction from NDSU. It is noted for its columnar shape and dense branching. It grows fast and can be used for screening, in boulevards, or as a specimen plant in the garden. It tolerates heat, drought and alkaline soils. The white-barked tree grows up to 40 feet tall with a spread of only 6–7 feet. Its tolerance to heat will make it less susceptible to borers.

‘Cupressina’ Norway spruce is a columnar evergreen with beautiful, dark green needles. It shows promise as a specimen tree in limited spaces; or it can be used as a windbreak when planted in groups. Norway spruce grows faster than most spruces and is less subject to diseases.

It’s hard to find a good evergreen for screening in urban landscapes. Arborvitae is often used, but its thin needles are sensitive to winter winds. The densely branched ‘Cupressina’ spruce seems to fit this niche. It grows 12–18 feet tall and spreads 12–15 feet wide. Norway spruce is hardy only to Zone 4 while the other three trees mentioned in this article are hardy in Zone 3 and can be grown anywhere in the state.

Now is a good time to chat with your local nurseries and landscapers. They can share more time with you now as you make your plans for the upcoming spring.

Does Sweet Clover Effect Heifer Pregnancy?

Some cattlemen in North Dakota have expressed concern with sweet clover potentially impacting conception rates in heifers due to phytoestrogens. Carl Dahlen and Fara Brummer, both animal scientists at North Dakota State University have reviewed literature relating to this possibility. The main source of their review is the Journal of Animal Science, a leading source of research information for animal science.

In reviewing the literature and in speaking with the USDA ARS Poisonous Plants Research Center in Utah, no documented evidence has been found in sweet clover when tested for phytoestrogens. However, there is always the possibility other compounds in sweet clover may exist with something else to impact fertility.

Cattlemen who are long in the tooth know very well the difficulty in having high heifer conception rates. Fifty years ago it was common to expose heifers to a bull only when they reached two years of age. Since then economics, improved nutrition, and genetic selection has enabled cattlemen to expect acceptable conception rates from heifers which are only 14-16 months of age. Granted conception rates may not equal that of mature cows, economics still favor breeding these young heifers at one year of age.

As a side note to this information from Dahlen and Brummer, I learned the sweet clover is a biannual food that was introduced for grazing purposes. Its technical name is melilotes officinalis. It actually is not a true clover. True clovers are of the trifolium genus and true clovers have been found to have phytoestrogenic effects. However, the same research report found in the Journal of Animal Science did not find sweet clover to have significant phytoestrogenic activity.

Although there was a time when planting sweet clover was a common practice to improve soil fertility and provide winter forage for animals, its days are past. There is plenty of research which indicates sweet clover has a very high demand for water when compared to other forage plants that can be grown under dryland conditions.

Happy New Year

On behalf of the staff in the NDSU Extension office of Williams County, including Mindy Sigvaldsen, Michelle Garcia and Mary Froelich I wish you and your families a very Happy New Year. I am sure 2015 will bring us some sad moments but our maker always opens a new window that will bring joy and happiness. Most of us are surrounded by strong family relationships and friends which will help us move forward. How lucky most of us are to have this support base because there are many who feel they must handle the tough times alone.