Pest Preventative Spraying of Conifers/Evergreens in Winter Dormancy

[Deleted member 47471]

A) Is it advisable and safe to preventatively spray my trees now in January to prepare for Spring, Summer etc. of this year?

B) Is Neem Oil application sufficient or is there another spray I should use?

C) How often should I spray them in this time period of preparation and when should I cease spraying?

 

[littletreefarmer]

Not necessarily helpful, but I'm going into my first Spring cycle of no spraying. I stopped late last Summer, and haven't seen any detriment yet. Obviously, tree vigor and constant monitoring and removal of insects is hugely important.

I feel like spraying chemicals for the sake of spraying chemicals is detrimental to my trees, my philosophy, and the environment. Lots of pros are leaning this way or already implementing no-spray regiments.

 

[stewarjm192]

So a few things from my experience in a very humid climate.....

bugs have never been to big of an issue, some adlegids/aphid issues, they aren't prevalent if I give enough airflow......but my biggest pest is needle cast on my conifers....mainly spruce and pine

I was told by a respected teacher that horticultural oils are detrimental to spruce, so I dont use neem, as much as id like to for its less toxic qualities....

I spray on a regimine for both fungus and bugs, switching up chemicals used, as id prefer to prevent issues, rather than try to chase my tail and fix issues......needle-cast on a ponderosa ruins that tree for years to come, so again, best to be preventative in my mind.

I would presume you live in a simillar climate to me in terms of humidity. I spray copper based fungicide on all my trees, which live in a plastic wrapped cold frame durring the winter once a month or so as preventative measures. The humidity is always super high in my cold frame, so ive had issues that id rather not repeat.

I tried a no spray life style, but I fear my climate may not allow this, or I just havent mastered my watering yet.....will I ever master watering?

 

[littletreefarmer]

I agree that fungal issues are more of a problem than insect issues. My biggest concern with no-spraying is the amount of rain we have gotten here over this past year. I'm hoping to be much more on top of water control for conifers this year, may even have to build some kind of structure to cover them from rain in general.

I'm finding that there are more directed and specific actions I can take to prevent the issues that spraying would generally protect from. Healthy trees are the first 90% of the solution.

 

[stewarjm192]

I agree, im moving most conifers to larger partical sizes, even for chuchin and small trees, with more pumice and lava

 

[Deleted member 47471]

Not necessarily helpful, but I'm going into my first Spring cycle of no spraying. I stopped late last Summer, and haven't seen any detriment yet. Obviously, tree vigor and constant monitoring and removal of insects is hugely important.

I feel like spraying chemicals for the sake of spraying chemicals is detrimental to my trees, my philosophy, and the environment. Lots of pros are leaning this way or already implementing no-spray regiments.

That’s fair. I listened to more recent Mirai content, and it seems to be true.

 

[Deep Sea Diver]

Simple questions in bonsai often lead to the most complex answers. This is one. Intend only to scratch the surface here.

Short answer is yes.

Long answer… as always… is it depends.

In this case it depends on:
- which trees are in your collection
- the actual hazard being present In the environment - look beyond one’s collection to the environment miles around
- the type of winter storage the trees are in. bench, ground, under bench, covered, cold frame greenhouse
- how crowded the trees are in storage
- air flow
- humidity
- climatic events
- drainage
- etc

In just one example: if one has both hawthorn and other fruit trees with junipers there is a very really threat of cedar apple rust infestation and transference between trees. Can destroy a juniper in short order if not proactively treated. Junipers can get CAR from host trees within about 300ft.

- We spray copper 3x during dormancy due to this threat. Also 2x in summer.

Skipping to Media drainage. Media with a larger particle size will indeed hold less water. Yet will foster larger, coarser root sizes, countering the need to get fine feeder roots and consequently fine ramification.

Proper pot drainage is even more important. It’s common in the PacNW to both chock up pots on one side to improve drainage during the rainy season And drill all four sides of all pots to prevent flooded areas.

Also water test pots in your collection for gpdrainage. Some, especially older pots… but also some newer ones have poor drainage and pool water in low spots. Was repotting a big ailing ancient pine a couple years ago. It was planted in a big low beautiful 200+ yoa Chinese pot. We discovered there was root rot in certain areas under the root ball. Water tested the pot on a level area and discovered pooling in the exact spots mirrored on the root ball.

Cheers
DSD sends

 

[Deleted member 47471]

Simple questions in bonsai often lead to the most complex answers. This is one. Intend only to scratch the surface here.

Short answer is yes.

Long answer… as always… is it depends.

In this case it depends on:
- which trees are in your collection
- the actual hazard being present In the environment - look beyond one’s collection to the environment miles around
- the type of winter storage the trees are in. bench, ground, under bench, covered, cold frame greenhouse
- how crowded the trees are in storage
- air flow
- humidity
- climatic events
- drainage
- etc

In just one example: if one has both hawthorn and other fruit trees with junipers there is a very really threat of cedar apple rust infestation and transference between trees. Can destroy a juniper in short order if not proactively treated. Junipers can get CAR from host trees within about 300ft.

- We spray copper 3x during dormancy due to this threat. Also 2x in summer.

Skipping to Media drainage. Media with a larger particle size will indeed hold less water. Yet will foster larger, coarser root sizes, countering the need to get fine feeder roots and consequently fine ramification.

Proper pot drainage is even more important. It’s common in the PacNW to both chock up pots on one side to improve drainage during the rainy season And drill all four sides of all pots to prevent flooded areas.

Also water test pots in your collection for gpdrainage. Some, especially older pots… but also some newer ones have poor drainage and pool water in low spots. Was repotting a big ailing ancient pine a couple years ago. It was planted in a big low beautiful 200+ yoa Chinese pot. We discovered there was root rot in certain areas under the root ball. Water tested the pot on a level area and discovered pooling in the exact spots mirrored on the root ball.

Cheers
DSD sends

I love it when you reply.

My answer:

Combination of JPN, DAS, CBD, BNS, and H. Cypress.

Cypress is outside, in ground, and currently has blackening on some lower tips (sigh-dense red clay and not enough oxygen? Too much burlap? Drainage issue? Remove from ground and repot??—another issue altogether)

All others are inside grouped close but gently in unheated garage, on top of blanket on floor, straw and pine bark added to insulate and protect root systems, a light flemsy single layer tarp hanging on either side with garage windows at house side and roadside doors allowing minimal light entry (not total darkness). I brought them all in when it hit 60F, 70F and stayed above/around 50F the past couple weeks. Otherwise they were grouped similarly outside next to porch in mostly shade and light tarp to shield from too much sun.

To water, I place a single shelf with holes and gaps in it on top of a plastic tote/bin and water, allowing good drainage into the tote underneath (since it’s been warm outside and I feared dormancy disturbance).

 

[Paradox]

A) Is it advisable and safe to preventatively spray my trees now in January to prepare for Spring, Summer etc. of this year?

B) Is Neem Oil application sufficient or is there another spray I should use?

C) How often should I spray them in this time period of preparation and when should I cease spraying?

My question is what are you spraying for?

Probably not much going on in your area in January unless its very mild.
Bugs and fungus usually arent a problem during the winter unless its a very mild winter.

For fungus and some kinds of insects, its good to apply dormancy spray prior to putting them into their winter storage area in the fall.
Once you take them out in the spring, spraying for fungus monthly from May - October is advisable if you live in an area prone to fungus, every 2 weeks when its humid and fungus has a better chance at infection. Some of us do an application of granular Bonide Infuse in mid to late April to get started

For insects, I spray only as needed when I have a problem.
the only exception would be for spider mites during the hottest part of the summer and for those I use a targeted product only for harmful mites, not a wide spectrum insecticide

 

[Deleted member 47471]

My question is what are you spraying for?

Probably not much going on in your area in January unless its very mild.
Bugs and fungus usually arent a problem during the winter unless its a very mild winter.

For fungus and some kinds of insects, its good to apply dormancy spray prior to putting them into their winter storage area in the fall.
Once you take them out in the spring, spraying for fungus monthly from May - October is advisable if you live in an area prone to fungus, every 2 weeks when its humid and fungus has a better chance at infection. Some of us do an application of granular Bonide Infuse in mid to late April to get started

For insects, I spray only as needed when I have a problem.
the only exception would be for spider mites during the hottest part of the summer and for those I use a targeted product only for harmful mites, not a wide spectrum insecticide

I wanted to know which product to use before I use anything preventatively for mites and or aphids. Is there something more prevalent or prone to attacks conifers and evergreen (other than Juniper borers)?

 

[Deleted member 47471]

My question is what are you spraying for?

Probably not much going on in your area in January unless its very mild.
Bugs and fungus usually arent a problem during the winter unless its a very mild winter.

For fungus and some kinds of insects, its good to apply dormancy spray prior to putting them into their winter storage area in the fall.
Once you take them out in the spring, spraying for fungus monthly from May - October is advisable if you live in an area prone to fungus, every 2 weeks when its humid and fungus has a better chance at infection. Some of us do an application of granular Bonide Infuse in mid to late April to get started

For insects, I spray only as needed when I have a problem.
the only exception would be for spider mites during the hottest part of the summer and for those I use a targeted product only for harmful mites, not a wide spectrum insecticide

That’s helpful, I’ll plan accordingly. Much appreciated.

 

[Deep Sea Diver]

I love it when you reply.

Thanks

My answer:

Combination of JPN, DAS, CBD, BNS, and H. Cypress.

Not sure what these are short of Hinoki Cypress . It’s ok to use widely used acronyms, especially after spelling them out in the same post though. A few are used as is JBP, JWP, JRP.

Cypress is outside, in ground, and currently has blackening on some lower tips (sigh-dense red clay and not enough oxygen? Too much burlap? Drainage issue? Remove from ground and repot??—another issue altogether)

The red clay soil in Virginia is a hazard for digging in bonsai. Used to come in the house covered with the stuff when landscaping, especially when it had rained. Guaranteed root issues. Likely your Hinoki is troubled

@rockm has a great method of avoiding this issue. Place bricks under the pots and mulch everything in.

All others are inside grouped close but gently in unheated garage, on top of blanket on floor, straw and pine bark added to insulate and protect root systems, a light flemsy single layer tarp hanging on either side with garage windows at house side and roadside doors allowing minimal light entry (not total darkness). I brought them all in when it hit 60F, 70F and stayed above/around 50F the past couple weeks. Otherwise they were grouped similarly outside next to porch in mostly shade and light tarp to shield from too much sun.

Garage storage methods depend on many things, including average temperature and tree type.
Having drainage, air circulation and keeping media a bit moist is important.

If most trees are dormant usually not an issue if temperatures average below 50F at times. Above that likely issues of breaking dormancy may kick in. But what the hey, one can’t fight Mother Nature. So have a contingency plan.

Anyways a bunch of folks here last year helped me craft an over wintering guide. I used azaleas as a focus, but the information and case studies are all applicable to all temperate trees. One might download this document and check it out.

cheers
DSD sends

 

[bwaynef]

One thing I haven't seen mentioned is how effective DORMANT sprays of Horticultural oil/Lime Sulfur are on reducing the pest/pathogen load DURING THE GROWING SEASON ...thereby reducing the need for other chemicals when beneficials are active and when you're actively managing the tree's growth so more likely to come into contact with residuals.

 

[stewarjm192]

One thing I haven't seen mentioned is how effective DORMANT sprays of Horticultural oil/Lime Sulfur are on reducing the pest/pathogen load DURING THE GROWING SEASON ...thereby reducing the need for other chemicals when beneficials are active and when you're actively managing the tree's growth so more likely to come into contact with residuals.

Could you clarify this a little

 

[Paradox]

I should have also mentioned that it is good to rotate between 2 different anti-fungal products.
For example, spray with a copper based product then at the next application (2 weeks or month depending on the situation) spray with something else like Daconil that is based on another compound

 

[Paradox]

One thing I haven't seen mentioned is how effective DORMANT sprays of Horticultural oil/Lime Sulfur are on reducing the pest/pathogen load DURING THE GROWING SEASON ...thereby reducing the need for other chemicals when beneficials are active and when you're actively managing the tree's growth so more likely to come into contact with residuals.

Probably because people dont use horticultural oil during the growing season?
The problem with dormant horticultural oil is that most (all?) tell you not to spray in the heat and direct sun.
Oil+heat & Sun = fried leaves/needles
Also spraying oil on the leaves and needles will clog the stomata and prevent gas exchange on the leaves.
This could effect the plant's ability to transpire and could cause some problems

 

[stewarjm192]

Probably because people dont use horticultural oil during the growing season?
The problem with dormant horticultural oil is that most (all?) tell you not to spray in the heat and direct sun.
Oil+heat & Sun = fried leaves/needles
Also spraying oil on the leaves and needles will clog the stomata and prevent gas exchange on the leaves.
This could effect the plant's ability to transpire and could cause some problems

this is exactly the reason I was warned against neem on spruce, although, the above would apply to anything with a stomata......

 

[ChristianDGreat]

I spray lime sulfur

 

[bwaynef]

Probably because people dont use horticultural oil during the growing season?
The problem with dormant horticultural oil is that most (all?) tell you not to spray in the heat and direct sun.
Oil+heat & Sun = fried leaves/needles
Also spraying oil on the leaves and needles will clog the stomata and prevent gas exchange on the leaves.
This could effect the plant's ability to transpire and could cause some problems

We're not communicating well. I'm not sure if that's on me or not.

Spraying Horticultural oil and Lime sulfur in winter seems to provide a big knockdown of pests/pathogens. That means there's less need for OTHER sprays (...of other chemicals?) during the growing season. I'm not advocating for spraying oils ...or anything else actually ...during the growing season. I'm singing the praises of dormant sprays ...during dormancy.

 

[Deleted member 47471]

Thanks


Not sure what these are short of Hinoki Cypress . It’s ok to use widely used acronyms, especially after spelling them out in the same post though. A few are used as is JBP, JWP, JRP.

The red clay soil in Virginia is a hazard for digging in bonsai. Used to come in the house covered with the stuff when landscaping, especially when it had rained. Guaranteed root issues. Likely your Hinoki is troubled

@rockm has a great method of avoiding this issue. Place bricks under the pots and mulch everything in.

Garage storage methods depend on many things, including average temperature and tree type.
Having drainage, air circulation and keeping media a bit moist is important.

If most trees are dormant usually not an issue if temperatures average below 50F at times. Above that likely issues of breaking dormancy may kick in. But what the hey, one can’t fight Mother Nature. So have a contingency plan.

Anyways a bunch of folks here last year helped me craft an over wintering guide. I used azaleas as a focus, but the information and case studies are all applicable to all temperate trees. One might download this document and check it out.

cheers
DSD sends

Is there anything I can do to try and preserve the Hinoki Cypress?