Mummy Berry Update 3/22/2021 – 3/28/2021

This weekly update provides information on the timing of apothecia (mushrooms) development from mummified overwintering berries in Washington’s Island, Snohomish, and Whatcom counties.

The first table shows the percentages of floral and vegetative buds at different developmental stages and indicates when susceptible tissue is available on the plants. The second table shows the apothecial developmental stages from mummies and when ascospores are produced.

Development of mummies and host reflect conditions occurring in one field from each of the three counties that are currently being monitored. There may be differences in the stages of development in other blueberry fields in these same counties, in different counties, or for different blueberry cultivars.

Host Developmental Stages

Week Beginning	County	Cultivar	Floral, Bud Break*	Floral, Tight Cluster*	Floral, Early Pink	Vegetative, Early Green	Vegetative, Late Green*
3/22/21	Island	Aurora	27	73	0	7	93
3/22/21	Island	Legacy	0	0	100	0	100
3/22/21	Snohomish	Reka	13	87	0	0	100
3/22/21	Snohomish	Liberty	37	63	0	50	50
3/22/21	Whatcom	Mixed	7	93	0	7	93

Percentages represent data collected from 30 plants per each cultivar.
*Red indicates a susceptible stage for infections.

Reference: Blueberry Growth Stages [Michigan State University]

Host Developmental Stages

Week Beginning	County	Cultivar	Floral, Bud Break*	Floral, Tight Cluster*	Floral, Early Pink	Vegetative, Early Green	Vegetative, Late Green*
3/22/21	Island	Aurora	27	73	0	7	93
3/22/21	Island	Legacy	0	0	100	0	100
3/22/21	Snohomish	Reka	13	87	0	0	100
3/22/21	Snohomish	Liberty	37	63	0	50	50
3/22/21	Whatcom	Mixed	7	93	0	7	93

Percentages represent data collected from 30 plants per each cultivar.
*Red indicates a susceptible stage for infections.

Reference: Blueberry Growth Stages [Michigan State University]