"Troubles come not in single staves, but in batallions." -- William Shakespeare, Macbeth

Insect and Fungal Pathogens

Pinus contorta contorta with pine nematode disease	Pinus contorta latifolia with Dothistroma Needle-Cast and Bagworms
LeContes Sawfly Larvae Damage	LeContes Sawfly Larvae
Introduced Sawfly Larvae (Not a problem)	Carpenter Ants in Loblolly (Secondary invader)
Emergent (right) and Sticky (left) Insect Traps	Armillaria Root Rot in Eastern White
Cerambycid Borer (secondary invader)	Ice storm damage (Pinus strobus)

What Bambi's Daddy did!
(deer damage to young loblolly pine)

"Primum non nocere." (First of all, do no harm) -- A Latin medical proverb.

To make a long story short, pathogens known at the pinetum will be merely listed, with very little commentary. So far the pinetum, considering the large number and concentration of different species of pine trees growing out of their normal ranges in this one place, has been one lucky pinetum (typed with crossed fingers).

But there have been some problems:

• pinetip moth
• sawfly larva (mostly Neodiprion lecontii)
• aphids (mostly on P. strobus)
• round-head (cerambycid) borers (? secondary invaders, mostly on crowded P. taeda)
• ips beetle (probable cause of rare P. resinosa drought mortality)
• pine webworm (seems to harm only seedlings)
• bagworm (very tough on all white pines and shore pine and lodgepole pine)
• pine needle scale (finally, almost totally eradicated by a little wasp)
• pine tortoise scale
• needle cast (assume Lophodermium)
• ?tip blight (Diplodia?) [(I hope this is wrong]
• red-band (assume Dothistroma)
• needle rust (Coleosporum)
• armillaria root rot (E. white pine)
• verticicladiella root decline (E. white pine)
• and untold unrecognized others.

No need to advise on therapy for these problems, because general advice in a specific setting may be very wrong. In general I have no philosophical bias against the use of chemicals when used wisely. The problem is that it sometimes turns out in retrospect that chemical use was probably unwise.

An example is bagworms, which were a problem for six years: Initially I sprayed extensively with Diazanon which, in retrospect, may have actually prolonged the bagworm siege by eliminating parasitic wasps or other natural balancing bagworm pathogens. B.T. worked one year and then seemed to have no effect the next year. The last year of this seige I had returned to only hand picking of bagworms on threatened trees (very time consuming), rarely augmented by spraying B.T. (which seemed to be working again) on heavily infested trees. In 1998, the bagworm problem finally abated and thereafter has been no problem.

The one instance of a seemingly unqualified "Good Chemical" has been the use of Cleary's 3336F (thiophanate) for needlecast, both Lophodermium and Dothistroma. This "saved" almost all of the affected jeffrey and ponderosa pine in the spring of 1994 and I used it again ('97 and '98 spring). The timing of spraying depends on the specific diagnosis (Please see File "#37. 1997 Field Notes" in the Directory). In addition, for needlecast, progressive bottom-upward pruning and interior thinning appears to be helping. Every January, the bottom tier of lateral branches and some of the interior branches are pruned.

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