Happy Spring! With warmer weather forecasted the next few weeks, it’s a great time to get outdoors! Raking leaves from lawns is a great activity this time of year for the whole family. You can also overseed bare areas of lawns right now. Don’t remove leaves or mulch from landscape beds yet. Leaves and dead tops of plants protect the plants and keep them dormant as long as possible. Warm sunny weather causes plants to break dormancy early and they become more susceptible to cold temperatures. If you’ve already cleaned up landscape beds, be prepared to cover plants again in the event of cold weather. If you have frosted tulip/daffodil foliage like mine, just leave them be for now.
Even though grass is greening up, it’s too early to apply fertilizers (ideally not till sometime in May). Mowing isn’t needed until after the grass begins to grow and requires mowing. Then maintain a mowing height of 3 to 3.5″ season-long. Pre-emergence herbicides targeted at controlling crabgrass and other warm season annual weeds shouldn’t be applied until soil temperatures consistently reach 50°F. It’s still too early. Soil temps can be found at: https://cropwatch.unl.edu/tags/soil-temperature
Wild/Bur Cucumber: In wet seasons like last year, wild and bur cucumber were seen overtaking windbreaks. These are fast growing, warm season annual vines. They die each fall and come back from seed which germinate and begin growth typically in May. Vines can be cut at the base if there’s only a few of them this spring. Many asked about chemical treatments last year. A pre-emergent control option for large shelterbelts is Simazine (Princep 4L) to kill weed seeds as they germinate. Don’t apply more than 4 qt. Princep 4L per acre (4 lb. a.i./A) per calendar year. Don’t apply more than twice per calendar year.
Renovating Windbreaks: Do you have a windbreak that has several dead or dying trees in it? Steve Karloff and Jay Seaton, District Foresters, shared to think 15-20 years down the road. What would be your goals for the windbreak (wind/snow protection; bloom time; fruit, nut, wood; wildlife/pollinator habitat, etc.)? Each situation will be unique, so these tips won’t apply to each one. Determine whether you’d like to remove the entire existing windbreak or do a partial clearing over time. For those choosing a partial clearing, they suggest to consider leaving the north and west rows and removing the south and east side for sunlight, establishment, and protection purposes. Stumps can be left (unless Scotch or Austrian pine), or can be removed. A stump treatment listed in the UNL Weed Guide is 2 qts of low vol 2,4-D per 10 gallons of diesel. Apply to point of runoff. Don’t use Tordon especially if you’re cutting out and stump treating elm or hackberry trees that get intermingled in trees you wish to save as the Tordon can affect the roots of those trees too. If existing trees, such as pines, have been trimmed up due to dead branches but the remainder of the trees are ok, one could simply consider adding a row of shrubs to cut down on wind.
Also, think about diversifying species based on one’s goals to ensure the windbreak isn’t eliminated due to pest problems. That’s something we’ve unfortunately had to deal with regarding Scotch and Austrian pines due to pine wilt. Conifer specie options include: cedar (most hardy), Ponderosa pine, and Norway and blue spruce. Shrubs include viburnums and hazelnuts; however, there are numerous species to consider depending on goals. Consider 3-5 rows as optimal with 1-2 rows as conifers, 1 row of hardwoods or tall conifers, and 1-2 rows of dense shrubs. However, there’s not always that kind of room available and that may not fit one’s goals. It’s helpful to stagger plant the trees in each row and the gaps can be filled with shrubs or the shrubs can be planted in one row. Next week I’ll share more on site preparation considerations.