Hi - I have the 16 Cryptomerias that were planted late October 2005. One of the recommendations was to make a grassless bed and cover, not too thick, with pine needles. I keep getting grass and weeds growing close to the trees. I need your advice how to kill the grass without harming the tree. We are working this weekend to kill off all grass, apply a weed barrier and restake the trees. How close to the trunk should I spray or should I just pull up the grass? Is there any one spray that is more effective and less damaging to the trees? I wish the nursey where I purchased them told me this in advance but they will remain nameless. Also Bermuda grass is starting to green and I've been killing it for a while. How should I address this type of grass? Will it continue to live under the pine needles and harm the trees? What is the proper way to stake this tree? Do they get the traditional stakes? I ask because unlike my Willow Oak that was planted at the same time, Cryptomeria's have lower limbs and a strong wind can easily cause damage. Your answers are much needed!
Why do you want to kill the grass? Is it at all possible there was a misunderstanding and that you were told grass would not grow underneath (due to a shallow root system, like maples or pines, for instance)? It seems very odd to me.
This was part of the original advice given in the thread Cryptomeria at Risk, started Jan. 14th. Take a look at that and let me know if I misinterpreted.
Well, I've actually now looked at two threads (the old one and a more recent one on another variety), and haven't seen anything about not growing grass. Maybe I missed something. But I really wouldn't stress about it as I don't think it's an issue. I think if your tree is doing well and being cared for appropriately otherwise, I would relax. It's 99% more likely that the grass will be affected by the tree, not the other way around.
Grass and trees don't actually don't get on too well, often one will be stunting or killing the ohter. Young, small trees need to have a large, grass-free area. Later they will shade out (kill) part of the grass, but not before they are big enough to case a large shadow.
Ron - how should I proceed? I keep getting grass and weeds growing close to the trees. I need your advice how to kill the grass without harming the tree. We are working this weekend to kill off all grass, apply a weed barrier and restake the trees. How close to the trunk should I spray or should I just pull up the grass? Is there any one spray that is more effective and less damaging to the trees? I wish the nursey where I purchased them told me this in advance but they will remain nameless. Also Bermuda grass is starting to green and I've been killing it for a while. How should I address this type of grass? Will it continue to live under the pine needles and harm the trees? What is the proper way to stake this tree? Do they get the traditional stakes? I ask because unlike my Willow Oak that was planted at the same time, Cryptomeria's have lower limbs and a strong wind can easily cause damage.
How much weed and grass are we talking here? What IS unhealthy for trees is to attempt to grow a lawn under trees. But letting a few weeds and grass duke it out with the tree here and there won't hurt a thing. Pull up what you can get and relax about the rest. Or are you talking about a carpet of weeds and grass? Bermuda grass is extremely resilient and will continue to survive (not thrive) under the trees. I'm a huge lover of the relatively selective Bermuda grass killer called "Over the Top". If you're living with Bermuda, this one needs to be in your arsenal.
For clarification, in the thread Cryptomeria Yoshino at Risk, advice was given to remove the mulch from the trunk, so assuming that you did that, but left the mulched area around all of the trees, then it seems that you are worried about grass that has grown into the mulched area around the trees as pictured in that thread? What did you use for mulch? It would be helpful if you posted a close-up picture of the situation now. I know little about the care of grass, but if indeed a horribly invasive grass has grown into that area, then from the picture it looks as though a gentle application of spray, if it is known to work on that particular invasive, can be applied without falling on the branches. For this you should be well acquainted with your sprayer; a sprayer which is used exclusively for herbicides. If not, personally I would recommended an inexpensive spray bottle, or Solo makes a rechargeable battery-operated spray bottle, which should be clearly marked "Herbicide" with a permanent marker. The spray bottle allows you to work up close and direct the spray right where you want it. To reiterate, it is wise to keep separate sprayers for herbicides - chemicals which kill plants - and fertilizers - chemicals which feed plants; the later can be used for fungicides and miticides as well. You sound as if you are definitely planning to do this job this weekend, but if there is any wind at all, don't spray. Go ahead and pull the grass up and remove the mulch from the trunks if that hasn't been done. If there is no wind and you do spray, then you are also well advised to wear entirely separate clothing, a mask, gloves, and goggles and remove and wash the clothes in a separate laundry load. As far as how close to the trunk to spray, it is my understanding that a product such a Roundup can be sprayed right next to the trunk, but personally I wouldn't do that. Work by hand that close to the trunk. Read the entire label of any product you choose to use and call the company with any questions that have not been answered. For example, if you plan to use Roundup on Saturday, and it rains on Sunday, the last information I have is that you will have to reapply the product again. It is good to be aware of the EPA Hazard Indicator for the products that you are using as well; it might influence your choice of which product to use. My last printed information on this allows for the following comparison: Class IV Toxic has a dermal LD of >20000 mg/kg, while Class II Moderately Toxic has a dermal LD >200 to <2000 mg/kg (LD=probable lethal dose). The Class IV oral LD is >1 pint, while the Class II oral LD is 1 tsp to 1 oz.
A little grass won't hurt. If there's a lot, hand-pull the bulk of it to get it down to a harmless level. No need to use poisons.
