- Dwarf Mistletoe Biology
- Hosts & Range (BC)
- Pine ... DMP - East of Cascades - Pl (Py)
- Hemlock ... DMH - West of Cascades - Hw (B, Ss, Hm); ... Pl
- Larch ... DML - S. Interior - Lw (Pl)
- Douglas-fir ... DMF - S. Interior - Fd (Bg)
- crude map
- Latin
- Arceuthobium
- americanum DMP
- tsugense DMH
- laricis DML
- douglasii DMF
- Biology
- Basic Facts
- leafless parasitic plant
- dioecious (♀ ♂)
- obligate ... tissue vigour; ... "dead branch"
- "long life cycle" & host specific ... climax forests
- aerial shoots are short-lived ... 3-5 yrs
- endophytic roots are perennial
- cortical strands (in phloem ... sugars)
- sinkers (get overgown in xylem ... water)
-
- fall - seed dispersal then OW
- 2 years - root system
- + 2 years - aerial shoots
- + 2 years - berry production
-
- Spread & Development
- seed prod'n varies ... latitude & elevation
- rate of spread
- clear shot - ~15m max
- <10m is typical
- then a 5-7 yr delay
- infected residuals?
- ave spread rates in a stand
- horz. ... 0.5-1.0 m/yr (dense vs. open ... LAI)
- vert. ... 0.4 m/yr (SI>22m @ 50yr is "OK")
- factors for intensification
- time to produce seed is slow (5-7 yr)
- crown still grows, infection inside crown, harder for seeds to "escape"
- LAI ... Hw vs. Pl
- very high rate in juvenile years
- targets grow
- targets get closer
- rate then slows - crowns close ... shade
- JS?
- brooms - not til tree is ~40 yr (self-pruning)
- development depends on
- continued presence of host
- species compostion?
- fire
- Hw - no fire ...
- Pl - intense fire ...
- Pl - low-mod intensity fire ...
- coastal Hw vs. interior Pl
- Damage
- ~2.5 million m3 for Pl & ~1.7 for Hw
- Hw& Pl, mod.-heavy infect. 20-40% loss
- Lw & Fd, mod.-heavy infect. 30-60% loss
- Volume Loss & Age
- < 40 yr - no sig. loss (too early)
- 40-60 yr - growth loss measurable
- 60-120 yr - can be sig. loss
- Quality
