30 Sep Fruit Collections and Seed Cleaning by Fallon Ross

Plant life is flourishing, and wildlife is active in the summertime. The season for fruit collecting begins every late-June until mid-September. Prior to collecting, the nursery employees scout for suitable locations nearby to gather fruit for cleaning, processing and storing the seeds. We must act quickly after the scouting period to avoid fruit losses due to birds, deer, and local foragers. Every year the nursery manager sets a target goal for the number of species needed for the season. Knowing the expectations for the season allows the collectors to devise a plan for the collecting frequency and which fruits to prioritize.

Before collecting the fruit, the site is examined. Some of the thickets where the shrubs are located are surrounded by poison ivy which encourages us to avoid collecting in those areas for safety precautions. I have had the privilege to assist the seasonal workers collecting American plum and Sand cherry. We observe the shrubs prior to picking. Typically, the seed has better chance to germinate and processes faster when the fruit is fully ripened. The American plum species can present all vibrant colors of yellow, pink, red and purple due to the species many varieties in Nebraska. Therefore, we pick according to sight and touch. We avoid picking fruits that are green, hard, or displays any characteristics of pest infestations and pathogens. Some pathological concerns would be….

Many of the fruits obtained are Chokecherry (Prunus virginiana), American Plum (Prunus Americana), Choke Berry (Aronia melanocarpa), Serviceberry (Amelanchier spp.), Elderberry (Sambucus canadensis) and Sand cherry (Prunus pumila) fruit along the public roads of central Nebraska. We also collect a small amount of Wood rose, Twin berry and Red elderberry.

(Flowering Choke Cherry photo provide by Richard Gilbert-Nursery Manager)

(Choke Cherry Fruit)

(American Plum Fruit)

(Choke Cherry photo provided by Bailey Maca-Horticulturist)

Once the fruit is gathered at the end of the workday, we inventory the weight and date the fruit was obtained. Keeping a record of our fruit supply helps to determine the fruit to seed ratio, cost estimations and estimate the amount needed to reach the quota for the season. Each fruit is stored at the seed bank in the stratification unit at around 34 degrees Fahrenheit to prevent any mold growth and preserve the seed’s integrity before processing the fruit. However, to limit contamination in the stratification unit and quickly ripen the American plum, the fruit is left at room temperature. The riper the fruit, the easier processing operation.

When handling the fruits each processing method varies according to the size of the seed each fruit contains.

Subsequently, the fruit is deconstructed to extracted the seed using two types of equipment: a food processor for seeds smaller than 3 mm (e.g. Elderberry fruit)  and a larger processor is used for the seeds 3 mm or more (e.g. American plum). Using the processor removes all of the skin and pulp on the fruit, revealing a clean seed. We then use a floating technique to separate the waste from the clean seed and indicate which seeds may be suitable for plant according to in density. The good seed typically sinks to the bottom of the container using the floating technique, however the procedure will not eliminate all waste or retain viable seeds. The water is drained and the seeds are left to air dry on a sieve tray. Most of our seeds warrant about 2-3 days for the seed coat to dry, we avoid completely drying out the seed to prevent moisture loss at the endosperm.

We record where, when, and how much fruit was collected each day to track our inventory. Surprisingly, our most abundant fruit collections were American plum and Sand cherry. Choke cherry and elderberry possibly had a poor pollination count this season, providing only a few pounds of seed compared to the hundreds of pounds of fruit collections. Eventually, the seeds are packaged and placed in the stratification unit to be planted in the Fall.