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unit28
08-25-2012, 03:02 PM
Just tested the ph and nitrates 4 weeks ago, showed it to be very alkaline and high nitrates. Sandy Loam

The cooler weather we had {slowing down KBG growth} made this one prevalant. Threw down gypsum to try and bring down the ph, It's been 20 days since ferted with syn 10-0-20 10%fe for growth regulation and color improvement. Aerated 1 week ago.

Irrigation on at 3am off at 630-- 1.25" of irrigated precipitation per week, daily ET at .18 Total rainfall 1" for August so far.

location of rust- right on the dripline of an ornamental birch East side of the tree where it is shaded afternoon. Color of lawn is very good, HOC 4"

I did trim the tree there 4 weeks ago and raised the canopy that was touching the lawn.

Over seeded, bumped the irrigation in this zone from 20 to 35 mns thinking of adding qr fert for a booster...thoughts?

RigglePLC
08-25-2012, 03:20 PM
Newly seeded perennial ryegrass is very susceptible to rust fungus in the fall. With a little luck rust will disappear about the date of your first frost (if it has not happened yet) (LOL!) Extra fert will help--particularly nitrogen.

Rust is not usually big problem, but some of the premium perennial rye types are more resistant to rust.

Think Green
08-26-2012, 05:57 PM
Threw down gypsum to try and bring down the ph???

Why did you use gypsum to change the ph...........it weakens saline and soften soil conditions without altering the pH.

No other comments..........!

Smallaxe
08-26-2012, 06:58 PM
KBG growth is enhanced with cooler temps after a long hot summer like this one, not the other way around... along with fescue and per. rye...

Now that it is cooler you should be able to shorten the length of the cut and it is excessive water sitting on the leaves, is one thing, that causes rust... it doesn't appear that low fertility is an issue here, so you might think about allowing the surface to dry off...

unit28
08-26-2012, 09:43 PM
Threw down gypsum to try and bring down the ph???

Why did you use gypsum to change the ph...........it weakens saline and soften soil conditions without altering the pH.

No other comments..........!
Mabey the applied terminology is laxed
tested soil sample showed an indication of locked {excessivly available}nutrients. PH was 8.5 thus....
After aerating the lawn that was irrigated at 1.25" per week, and having dry plugs totally crumbled to dust around the V/Ball court, sloped areas, directly around walkways , driveways, and parkways


added gypsum to start converting some hard packed alkaline soil into something more beneficial long term. It's only a single application in my simple holistic scheme.

unit28
08-26-2012, 10:21 PM
KBG growth is enhanced with cooler temps after a long hot summer like this one, not the other way around... along with fescue and per. rye...
Now that it is cooler you should be able to shorten the length of the cut.
--
It has not been hot around here. Mostly 85*.
Just about 0 moisture this month other than irrigation.
This has been the coolest August on record I think. We've seen alot of low temps in the 40's and even went as low as 37* on the 16th.
Even with that as a given there was a deficet of 5" of precipitation due to daily evap...There was guttation going on at it's best
So we were at below optimal growing temps.

Now one week later we hit 90* with high humidity.
Total opposite of the spectrum. This weekend, you could see overnight complete lawns just falling over. Lawns are dropping like flies now.
This coming week temps will be back into the upper 80's with 90* coming in for the majority or later half..

and it is excessive water sitting on the leaves, is one thing, that causes rust... it doesn't appear that low fertility is an issue here, so you might think about allowing the surface to dry off...
--

Did change the start time to 6am. Other than that I'll need something to outpace the fungus, and promote growth. I don't wanna, but I'll be bagging clippings here as well. about 12.5K's worth.

RigglePLC
08-26-2012, 10:57 PM
Rust doesn't need much water to spread...a heavy dew at night will result in spread of rust. It is a fall disease; it must spread up north from Mexico every year; killed by frost. Slow growth such as seen under cool dry conditions favors rust.
Rapid growth, such as seen under warm moist conditions with high nitrogen levels often results in outgrowing the rust. Some types of bluegrass and some types of rye are more resistant to rust. You get a lot of red dusty spores. The orange-red dust gets on your shoes and equipment. Rust is not a major problem--not compared to lack of rain. Plan to add extra fert just after frost--this timing helps the grass recover as the rust fades out.
http://pickseed.com/usa/proTurf/turf/index.html
Fiesta 4 has good resistance to rust disease. Do not use types than have no claims of rust resistance.

unit28
08-27-2012, 07:59 AM
yes, we are right in line with the southerlies from the South. Have been for the majority of this season...

I'm wondering if the guttation has something to do with it.
I'm sure it's part of natures simple holistic scheme as well....lol

I've taken stems and rubbed them on a napkin, and cruised into the infected area with white tennis shoes....it's not showing any sign of spore dis-coloring.

The grass isn't sticky in the afternoon when I've checked it, but that rust seems stuck on there really good and not even rubbing off between my fingers.

I'll try to snap a pic of the area later.
Thanks for the replies y'all.

Smallaxe
08-27-2012, 09:29 AM
Now you speak of guttation during the same period of time the weather is dry... your turf is not dry with irrigation so what the weather is like is irrelavent... then you speak of walking through with white tennis shoes and showing no signs of rust disease...

We should slow down and think about this a bit... :)

unit28
08-27-2012, 04:19 PM
yes, the soil in areas of recreation, slopes and around cement were very dry.
If our precipitation for the month is 1" and the daily et rate is .18...after 28 days how much does that equate too?
-5 inches or something like that.
If I'm watering at 1.25 inches per week, that's 5 inches as well.


did I find guttation? Today at about 10AM
Sprinklers have been off since Saturday.
Maybe I'm overthinking the rust spot....sigh

1.}pic of guttation?
2.}rust?
3.}and general appearance

Smallaxe
08-28-2012, 10:43 AM
So you have a lot of water in those areas and that is your issue,,, forget about the dry summer...
Based on the following article I would let the lawn dry out to normal levels, fertilize it and let it come back to normal fall growth...

"Rust, caused by Puccinia spp., is not seen every year, but sometimes becomes severe on susceptible varieties during hot periods of the summer when grass growth is reduced. When rust is severe, the lawn may have a yellowish to reddish-orange appearance. A red-orange dust fills the air when the grass is mowed and also collects on shoes and clothing. Individual blades of grass will have slightly elongated yellow-orange to red-orange spots or pustules (filled with a rusty colored powder -- the spores of the rust fungus) that break through the leaf surface (figure 11). When rust is severe, the grass blades turn yellow, wither and die. Rust may also weaken a lawn, making it more susceptible to winter kill the following winter.

Rust is favored by humid weather with night temperatures of 70-75 F, day temperatures of 85-95 F, wetness from dew lasting many hours after sunrise, and frequent light rain (or watering). Rust may be especially severe on Merion and Touchdown varieties of bluegrass, which are highly susceptible. When weather favors rust, the disease is more likely to be severe on low maintenance lawns -- lawns with low soil fertility and some degree of drought stress. It is also apt to be a problem in shady areas, on closely cut grass, and on newly laid sod.

Rust is easily controlled by maintaining good lawn growth with adequate fertilization and adequate watering. Once normal growth is obtained, mow the grass frequently at recommended mowing heights and remove the clippings, an important source of the rust fungus. Fungicides are not usually needed or economical for homeowners, but may be required to help protect new growth when rust is severe and weather promotes rust development. "

unit28
08-28-2012, 09:27 PM
I'm sure the irrigation is right on par with average watering requirements of KBG.
The heads are .4" pr hour, head to head spacing is = to .8 pr hour
Running at 1/2 hour --- .4" x 3 days week = to 1.2 " irrigation weekly
The daily average et comes out to .18 x 7 days is 1.26" evaporation weekly

With the compaction it needed to stay moist with regular watering. we're working on the soil condition to change that for an improvement on nutrient uptake, make deeper roots and obtain less frequent watering.


The site of origin of the rust was under a tree canopy that was dense, on the ground and covering 100sq feet. The only thing going for that area was watering it. No fert etc has touched that area since I've maintained it for 4 years.

This area besides the other dry locations was , shaded, less nutrition availability, and compacted.
I raised the canopy and started maintaining it, the low temps came and
now fungi is there...not all over yet.

I've mowed it every Friday morning and have never seen it wet
except when the low temps came...probably dew. That's why I have the question mark by my guttation pic. I have no reference as to what guttation looks like on a KBG blade.

Another thing came to mind is they installed themselves a new landscape bed. Now I'm wondering if they aren't farkin with the sprinklers to try and establish some new plants.

When I aerated i made a one pass with added gypsum. Maybe need to really open the soil up more, and not sure about adding sand. They are a large family with a lab who entertain guest through the summer, v/ball court on turf and ask to keep the grass cut high.

http://www.extension.purdue.edu/extmedia/BP/BP-110-W.pdf

Rust outbreaks are most common in late
summer and early fall, although sometimes the
disease is active in the early spring (especially on
poorly nourished turf). Rust is a disease of slow
growing turf, so factors that contribute to poor
growth tend to favor rust development. Such
factors include summer heat and drought stress,
low nitrogen fertility, compaction, and shade.

Not really saying anything about water, but thay all say water adequatly . I'm sure that's to promote vigor.

http://ipm.illinois.edu/landturf/diseases/turfgrass_rust/index.html

Basidiospores are transported by air currents to the leaves of nearby, alternate hosts (mostly woody shrubs and herbaceous ornamentals), where they may germinate and infect resulting in two more spore types, pycniospores, and later, the aeciospores. Cluster cups or aecial form on the alternate hosts and release aeciospores which are then capable of infecting grass plants giving rise to urediospores, thus completing the disease or life cycle. The urediospores are most important in infection of mowed turfgrasses.

Infection for most rusts is favored by 4 to 8 hours of low light intensity, temperatures of 70 to 75F (21 to 24C), and high humidity, heavy dews, or light rains followed by 8 to 16 hours of high light intensity, temperatures of 80 to 95 F (27 to 35C), and slow drying of leaf surfaces.

Smallaxe
08-29-2012, 07:26 PM
If it hasn't been fertilized for 4 yrs., then why wouldn't you change that, since low N turf seems to be subject to rust???

unit28
08-30-2012, 09:06 AM
If it hasn't been fertilized for 4 yrs., then why wouldn't you change that, since low N turf seems to be subject to rust???

The lawn already has high nitrates I tested the soil. I used 26% insol {SR} syn N for previous years total of 3#sK annually. I'm sure the ph as we all know causes some issues with uptake and also the soil being compacted has the other side of it holding excess compounds.

I switched later this year to 10-0-20 {SR} since July. This tree canopy was lifted Aug first week.

my first post was asking about using a QR fert meaning 1{N}-0-0

Now, I'm not using that route.

Mscotrid
08-30-2012, 11:48 AM
Great thread very informative dialog. What rate of gypsum are you applying?