Agreed Upon Summer Stress Effects and Realistic Expectations of Growing Grass in Richmond
Richmond is a part of the U.S. that is called the “transition zone”. “You can grow any grass in the transition zone, you just can’t grow any grass well.” This is especially true for the type of fescue grass that most home owners grow in Richmond. The most stressful time of the year for fescue is the summer months. The climatic trend has extended summer like weather further into September which has increased the length of stress. Summer stress is caused by persistent day time temperatures over 90 degrees, night-time temperatures above 70 degrees, and relative humidity above 70%. At high relative humidity, the fescue is much less able to effectively cool itself and as a result is even more prone to heat buildup and direct heat injury. Prolonged high night time temperatures result in less root production, rapid root maturation, and die-back. This results in lawns thinning out and becoming more light green.
Summer Stress Diagnosis Challenge
Heat stress injury makes the fescue more vulnerable to damage from other summer related stresses (e.g.; mowing, traffic, trees etc.). As a result, heat related injury and turf decline is often a result of a complex of individual factors interacting to cause more summer problems than each individual stress factor (see Table 1 below) acting alone. The industry calls this summer stress complex. For this reason it is often difficult to get a handle on specific causes of summer decline. Summer heat stress factors are out of our control and are the key underlying issue in summer turf decline. Stress factors are additive. Adding just one additional stress factor (Table 1) can be the tipping point. Adding two or more stress factors will nearly guarantee summer decline. For example, a lawn that is mowed low, located near a tree, and is oriented towards the sun on a slope will lead to decline every season. The “DNA” of each lawn is unique. Most lawns have micro-areas where two or more factors come together to create areas that perpetually decline in the summer (and are a ghost of the former spring glory).
Common Summer Stress Factors
Environmental Factors
Cultural Practices
Site-Specific Factors
Day time temperatures
Mow height, dull blades
Trees
Night time temperatures
Mow frequency
Traffic/wear (mower, pets, kids)
Humidity
Mow time of day
Shade (buildings & trees)
Excess rain
Herbicide injury
Slope
Cloudy cover
Irrigation (time of day, run time)
Drainage
Cold
Nutrition (too little, too much)
Soil (shallow topsoil, rock, clay)
Wind
Disease
Pet waste
Extremes wet/dry, early/late
Insects
Sun Orientation (south, morning)
Abrupt weather changes
Tree trimming/pruning
Air movement
Memory Affect
Mild spring climatic conditions can hide injury and stress. In the spring, grass can be injured/stressed and quickly recover, but these areas that “recover” will manifest problems in the summer. We call this a “memory effect”. This is similar to an injury sustained when your 16 years old that comes back to trouble you when you get older. Commonly observed Spring memory effect stress events are as follows:
Party with extra traffic, kid pool, slip-n-slide,
Clumps of heavy grass clippings
Irrigation issue, temporary drought
Pet urine/feces
Leaf debris piles
Repeated car tire traffic
Home construction debris left on lawn
Remodeling project traffic
Bags of mulch/topsoil left on lawn
Detergents from cleaning (sidewalk, siding, cars)
Mowing low, intentional or accidental
A lawn mowed low in the spring has shorter roots and enters into summer in a weakened condition and is more prone to summer decline. These memory effects lead to confusion when trying to diagnosis causes for summer lawn decline. Lawn needs to enter into summer in peak condition in order to prevent decline in July/August. In summary, Spring/Fall (cool/mild weather) hides weak grass and poor site specific conditions.
Mowing Height Definition
The most damaging stressor is mowing because it is a weekly injury (death by a 1,000 cuts). The length of the grass blades corresponds directly to the depth of the roots. The highest setting on most mowers is too low. Lawns need to be maintained 4.0 to 4.5 inches. Most mowers will not mow higher than 3.5 inches. The difference between 3.5 to 4.0 inches is amazing. The difference between 3.5 to 4.5 inches is HUGE. Lawn areas inaccessible by a mower are line trimmed. These areas are cut even shorter (1 to 2 inches) in some of the most environmentally stressed areas of the lawn (e.g. mailbox, curbs, sidewalk, along foundation of buildings, etc.). Height control of a line trimmer is poor. Mowing height is not determined by a setting on the mower, but is determined with a ruler.
Biological & Non-Biological Factors
Stress factors can be more simply grouped into biological and non-biological factors. Biological factors include living organisms like health, disease, insects or heavy weed populations, and are often the cause of erratically unhealthy lawns. Lawn by Dr Vaughan’s service treats for biological problems. Biological problems they are generally easy to treat (herbicides for weeds, fungicides for fungi, etc.), inexperienced turf managers or homeowners often jump to conclusions and misdiagnose the core problem as biological when they’re really not. And it’s understandable! After all, if you went to the doctor feeling unwell, you’d rather take a pill and be on your way than go in for surgery. But reality is usually more complex. Non-biological stress factors are usually site-specific (e.g. soil depth, shade, tree competition, slope, drainage, orientation, etc). A stress free lawn can naturally fight off disease and insects pressure. When the lawn becomes become more stressed from the hot/humid summer plus non-biological stress factors, it needs Lawns by Dr Vaughan’s help. However, many lawns will have areas that repeatedly decline each year. In such situations, the non-biological stress factors are so severe that it’s not realistic to prevent. Non-biological stress factors are more expensive to fix and/or less controllable or preventable (e.g. weather, home orientation). For example, the time and expense of correcting the following problems can be significant:
Improperly graded lot corrected by regrading
Shallow top soil corrected by adding topsoil (3-4 inches)
Mowing low corrected by buying a new mower with higher settings
Irrigation spray pattern blocked by plants/fence corrected by moving irrigation heads
Tree shade/root competition corrected by removing trees
Drainage issues corrected by installing drainage
Traffic patterns corrected by installing pavers
Pet waste/traffic corrected by training or rehoming
Some of these abiotic factors point to homeowner issues that can come across as “blaming” when being explained. Unfortunately, these abiotic factors are more often the cause of the injury which further adds to uneasy conversation with client. These problems can become very personal. Lawns by Dr Vaughan does not control and/or correct abiotic factors. Fall reseeding is a cheaper short term solution (1 year) than correcting abiotic factors; however, in the course of 10 to 15 years, the cost of reseeding every year could exceed the cost of correcting the abiotic factor.
Lawns by Dr Vaughan’s Role
When the growing conditions are stressful, there is a greater need to “assist”, or intervene, with higher mowing heights (>4 inches), proper irrigation, nutrition, insect, and disease control. Lawns by Dr Vaughan is assisting with the irrigation, nutrition, insect, and disease control. These treatments reduce the effects of summer stress complex, but don’t eliminate it. If excess shade is the problem, sunshine will only fix it. Lawns by Dr Vaughan can’t spray sunshine. The majority of the yards that we treat get through the summer with just a few “dents and bruises”. Some lawns have reoccurring areas that “die out” every year. In such situations, it would be best to select another type of ground cover that is better suited for that area (e.g.; plant warm season grasses, create an ornamental bed, plant a tree, create a water feature, xeriscape, potty train pets to use a non-grass area, relocate trampoline).
In summary, summer environmental stress is a reoccurring problem in Richmond. Some summers are harsher than others. In the Spring and Fall, site specific stress factors and cultural stressors are not exhibited as a problem until summer heat kicks in. This leads to confusion in the summer. “What happen to my yard” comment in August can be ultimately blamed on summer heat stress pushing the lawn over the edge when coupled with the added site-specific stress factors. Fall aeration/reseeding is one of the most important cultural practices to help the lawn recover from the Virginia’s brutal summer heat and humidity. If your lawn doesn’t need to be aerated and reseed, you are fortunate. Most lawns will struggle and need aeration and reseeding to restore the lawn in the Fall.
Summer Stress & Realistic Expectations
Agreed Upon Summer Stress Effects and Realistic Expectations of Growing Grass in Richmond
Richmond is a part of the U.S. that is called the “transition zone”. “You can grow any grass in the transition zone, you just can’t grow any grass well.” This is especially true for the type of fescue grass that most home owners grow in Richmond. The most stressful time of the year for fescue is the summer months. The climatic trend has extended summer like weather further into September which has increased the length of stress. Summer stress is caused by persistent day time temperatures over 90 degrees, night-time temperatures above 70 degrees, and relative humidity above 70%. At high relative humidity, the fescue is much less able to effectively cool itself and as a result is even more prone to heat buildup and direct heat injury. Prolonged high night time temperatures result in less root production, rapid root maturation, and die-back. This results in lawns thinning out and becoming more light green.
Summer Stress Diagnosis Challenge
Heat stress injury makes the fescue more vulnerable to damage from other summer related stresses (e.g.; mowing, traffic, trees etc.). As a result, heat related injury and turf decline is often a result of a complex of individual factors interacting to cause more summer problems than each individual stress factor (see Table 1 below) acting alone. The industry calls this summer stress complex. For this reason it is often difficult to get a handle on specific causes of summer decline. Summer heat stress factors are out of our control and are the key underlying issue in summer turf decline. Stress factors are additive. Adding just one additional stress factor (Table 1) can be the tipping point. Adding two or more stress factors will nearly guarantee summer decline. For example, a lawn that is mowed low, located near a tree, and is oriented towards the sun on a slope will lead to decline every season. The “DNA” of each lawn is unique. Most lawns have micro-areas where two or more factors come together to create areas that perpetually decline in the summer (and are a ghost of the former spring glory).
Common Summer Stress Factors
Memory Affect
Mild spring climatic conditions can hide injury and stress. In the spring, grass can be injured/stressed and quickly recover, but these areas that “recover” will manifest problems in the summer. We call this a “memory effect”. This is similar to an injury sustained when your 16 years old that comes back to trouble you when you get older. Commonly observed Spring memory effect stress events are as follows:
A lawn mowed low in the spring has shorter roots and enters into summer in a weakened condition and is more prone to summer decline. These memory effects lead to confusion when trying to diagnosis causes for summer lawn decline. Lawn needs to enter into summer in peak condition in order to prevent decline in July/August. In summary, Spring/Fall (cool/mild weather) hides weak grass and poor site specific conditions.
Mowing Height Definition
The most damaging stressor is mowing because it is a weekly injury (death by a 1,000 cuts). The length of the grass blades corresponds directly to the depth of the roots. The highest setting on most mowers is too low. Lawns need to be maintained 4.0 to 4.5 inches. Most mowers will not mow higher than 3.5 inches. The difference between 3.5 to 4.0 inches is amazing. The difference between 3.5 to 4.5 inches is HUGE. Lawn areas inaccessible by a mower are line trimmed. These areas are cut even shorter (1 to 2 inches) in some of the most environmentally stressed areas of the lawn (e.g. mailbox, curbs, sidewalk, along foundation of buildings, etc.). Height control of a line trimmer is poor. Mowing height is not determined by a setting on the mower, but is determined with a ruler.
Biological & Non-Biological Factors
Stress factors can be more simply grouped into biological and non-biological factors. Biological factors include living organisms like health, disease, insects or heavy weed populations, and are often the cause of erratically unhealthy lawns. Lawn by Dr Vaughan’s service treats for biological problems. Biological problems they are generally easy to treat (herbicides for weeds, fungicides for fungi, etc.), inexperienced turf managers or homeowners often jump to conclusions and misdiagnose the core problem as biological when they’re really not. And it’s understandable! After all, if you went to the doctor feeling unwell, you’d rather take a pill and be on your way than go in for surgery. But reality is usually more complex. Non-biological stress factors are usually site-specific (e.g. soil depth, shade, tree competition, slope, drainage, orientation, etc). A stress free lawn can naturally fight off disease and insects pressure. When the lawn becomes become more stressed from the hot/humid summer plus non-biological stress factors, it needs Lawns by Dr Vaughan’s help. However, many lawns will have areas that repeatedly decline each year. In such situations, the non-biological stress factors are so severe that it’s not realistic to prevent. Non-biological stress factors are more expensive to fix and/or less controllable or preventable (e.g. weather, home orientation). For example, the time and expense of correcting the following problems can be significant:
Some of these abiotic factors point to homeowner issues that can come across as “blaming” when being explained. Unfortunately, these abiotic factors are more often the cause of the injury which further adds to uneasy conversation with client. These problems can become very personal. Lawns by Dr Vaughan does not control and/or correct abiotic factors. Fall reseeding is a cheaper short term solution (1 year) than correcting abiotic factors; however, in the course of 10 to 15 years, the cost of reseeding every year could exceed the cost of correcting the abiotic factor.
Lawns by Dr Vaughan’s Role
When the growing conditions are stressful, there is a greater need to “assist”, or intervene, with higher mowing heights (>4 inches), proper irrigation, nutrition, insect, and disease control. Lawns by Dr Vaughan is assisting with the irrigation, nutrition, insect, and disease control. These treatments reduce the effects of summer stress complex, but don’t eliminate it. If excess shade is the problem, sunshine will only fix it. Lawns by Dr Vaughan can’t spray sunshine. The majority of the yards that we treat get through the summer with just a few “dents and bruises”. Some lawns have reoccurring areas that “die out” every year. In such situations, it would be best to select another type of ground cover that is better suited for that area (e.g.; plant warm season grasses, create an ornamental bed, plant a tree, create a water feature, xeriscape, potty train pets to use a non-grass area, relocate trampoline).
In summary, summer environmental stress is a reoccurring problem in Richmond. Some summers are harsher than others. In the Spring and Fall, site specific stress factors and cultural stressors are not exhibited as a problem until summer heat kicks in. This leads to confusion in the summer. “What happen to my yard” comment in August can be ultimately blamed on summer heat stress pushing the lawn over the edge when coupled with the added site-specific stress factors. Fall aeration/reseeding is one of the most important cultural practices to help the lawn recover from the Virginia’s brutal summer heat and humidity. If your lawn doesn’t need to be aerated and reseed, you are fortunate. Most lawns will struggle and need aeration and reseeding to restore the lawn in the Fall.