by Nanette Londeree, Master Rosarian
SIGNS
No discernable signs
SYMPTOMS
Emerging leaves in spring are balled or curved on very short shoots with conspicuous and extensive vein-clearing
Shoot tips becomes severely rosette
Plant growth is slow
Symptoms disappear later in season
CAUSE
The causal agent (or agents) is unknown, possibly a virus
OPTIMAL CONDITIONS
Transmission is by bud-grafting
No natural spread has been observed
TREATMENT
Prevention:
Because spread is almost exclusively during budding and grafting operations, control of this disease rests primarily with the nursery and commercial rose grower
Purchase high-quality, certified, virus-free or resistant nursery stock from reputable, reliable sources
Elimination:
No known treatment
If plants demonstrate symptoms, provide proper cultural care to improve plant vigor or replace infected plants if their growth is unsatisfactory
GOOD GUY / BAD GUY?
Moderately bad guy; if symptoms disappear later in the season and plant recovers, then it’s a short term bad guy
If the plant does not recover, it’s an obvious really bad guy.
Photos of Spring Dwarf are by Baldo Villegas from the extraordinary website: http://members.tripod.com/buggyrose/irosepests.htm