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What’s good and bad for what

Never use colored mulches near annuals, shallow-rooted trees and shrubs or herbaceous perennials. These mulches are made using raw wood that serve as a source of food for microorganisms once it comes in contact with the ground. Microorganisms are better able to absorb nutrients in wood than are the roots of plants. As a result of the competition, plants — including weeds — starve and die. 
    Use colored mulches only around well-established deep-rooted trees and shrubs, for making pathways, sitting areas and playgrounds.
    Use hardwood bark mulches with caution.
    Unlike pine mulches, hardwood bark mulches contain up to 60 percent cellulose, which means they will decompose and rob nutrients from plants. They will also raise the pH of soils, making them less acidic. Repeated applications of hardwood bark can also result in the accumulation of manganese. When this occurs, the roots of the plants lose their ability to absorb iron and plant growth declines. Over the years I have seen numerous instances where the manganese and pH levels in the soil were so high that the only solution was total replacement of the soil.
    As you shop for pine bark mulch, be aware that not all bark mulches contain 100 percent bark. Some are made by blending one part pine bark and two parts wood chips. These blends are kept moist and turned periodically until the entire mass turns brown like bark.
    The truth is revealed if a piece of its wood reveals a yellow to light-brown center when broken. Once applied, fake bark mulches are more easily identified: After they have weathered a few weeks, the tannin-treated raw wood begins to lose its dark brown color.
    If that’s what you’ve got, the brown-colored raw wood will feed microorganisms, not plants.
    I was once called to investigate problems resulting from a mulch sale sponsored by a grocery chain. A large trailer load of double-shredded hardwood bark mulch had been trucked in and sold at cost. Buyers were immediately returning the mulch, complaining that it was killing their plants instantly.  Inspecting the load of mulch remaining in the trailer, I found it contained wood alcohol. I proved the presence of alcohol by cutting open a bag and throwing in a lighted match. The mulch immediately caught on fire. The mulch had been bagged while it was composting under anaerobic conditions, resulting in the formation of wood alcohol.
    Marble chips should not be used around plants that require acid soils. Marble chips are essentially chunks of limestone rich in calcium oxide, which will result in making the soil less acidic and eventually alkaline. That will be the death of acid-loving plants such as azaleas, rhododendrons, mountain laurels, andromeda, skimmia and Japanese hollies.
    Marble chips are safe around alkaline-preferring plants such as junipers, yews, pines, spruce and cherry laurel.
    Avoid using bluestone. I have seen numerous cases where plants have been killed after bluestone mulching. Like marble chips, bluestone contains high levels of calcium oxide. It may also contain metal contaminants, including nickel. The symptoms often go undetected for several years, by which time the damage is irreversible.


Ask Dr. Gouin your questions at DR.FRGouin@gmail.com. Please include your name and address.

The mystery of a great white’s whereabouts

Is the Bay becoming a haven for great whites?
    Great white sharks are huge flesh-eating machines that swim at speeds up to 35mph and travel the oceans of the world to satisfy their appetites.
    On May 29, a great white known as Mary Lee was reportedly detected in central Chesapeake Bay between North Beach and Tilghman Island. The predator would normally prefer the salty waters of the Atlantic Ocean. So what would make Mary Lee swim more than 100 miles up into the brackish waters of the Chesapeake?
    Mary Lee is part of a global shark-tracking program led by the non-profit company OCEARCH, which aims to increase our knowledge of sharks while benefiting public safety and awareness.
    Mary Lee’s whereabouts are monitored by a transmitor attached to one of her fins. The transmitor has to be above water for a certain amount of time to give the satellites a precise location and register a ping. The longer it’s above the water, the better the ping.
    In addition to the ping from the Bay that weekend, four additional pings were received placing Mary Lee in the ocean off the coast of New Jersey. Four pings trump one.
    A good ping can correspond very closely to the shark’s actual location — within 250 meters. But a bad ping can be miles off, or even indicate that the shark is on land.
    It’s unlikely that Mary Lee visited the waters off of North Beach. But it’s not impossible. We still have a lot to learn about the migration patterns of great white sharks. Learn more at www.ocearch.org.

It’s not there just to look pretty

Good mulch should be dark brown, persist for at least one growing season, be compatible with all the plants in the landscape and control weeds by suffocation only. Superb mulch does all that plus providing slow-release nutrients to feed the plants it is mulching.
    Mother Nature provides us with an abundance of mulches every fall. Fallen leaves and pine needles are excellent mulches satisfying every standard except being dark brown.  I have never purchased a bag of mulch in my life. Leaves are my mulch. When they decompose, nutrients are released into the soil, thus feeding the roots of mulched plants.
    Bark mulches do not contain any of the major nutrients used by plants except for calcium. But bark can contain essential trace elements, such as manganese, that can accumulate in the soil and cause problems. Thus it is important to choose mulch that is compatible with the species of plants being mulched.
     If you insist on purchasing brown mulch, I recommend pure pine, spruce or fir bark mulches. These contain 90 to 100 percent lignins, a source of carbon not easily digested by microorganisms. Thus they do not decompose readily and last on the surface of the ground one to two growing seasons. These mulches also contain polyflavanoids, which are beneficial because they help make essential trace elements available to the roots.
    Pine bark is available as nuggets, ground or as pine fines. The nuggets and ground mulches are the most preferred. Pine fines are generally only recommended as a soil amendment to increase the organic matter and help in lowering the pH of soils. Pine mulches are acidic in nature.
    Pine needles can be used as mulch but have a limited life, lasting only two to three months.
    Pea stone makes good mulch providing it is laid over landscape fabric. Brick chips, volcano slag or crushed granite are also usable mulches. But because of their density, they will sink into the soil unless they are placed over landscape fabric. 
    In the vegetable garden, straw — not hay — works as mulch. Even newspapers can be used, applied in 10 to 15 layers and soaked with water immediately to stop them from being blown away. I use shredded paper because it is easier to spread and, once soaked with water, remains in place better than sheets of newspaper. You need not worry about the ink because most black ink is made from soy while the colored inks are organic. I would prefer the old zinc ink because most of our soils here in the East are low to deficient in zinc, a mineral important in our diet.
    Shredded cardboard also makes good mulch. The advantage of using straw, newspapers, shredded paper and cardboard is rapid decomposition without creating nutrient stress. As they are opaque, they control weeds by the shade they create.
    Black plastic and landscape fabric also make good mulch. Black plastic mulches prevent the loss of water by evaporation. But these must be removed at the end of the growing season. Landscape fabric has another drawback in that weeds such as Bermuda grass, pig weed and nut sedge can grow through the fabric, making it impossible to pull them without damaging the fabric. Removing the fabric at the end of the season is also harder because of weeds that have grown through it.
    Next week, I’ll give you more reasons to avoid other mulches.


Ask Dr. Gouin your questions at DR.FRGouin@gmail.com. Please include your name and address.

So many variables are at play it can sometimes be baffling

We arrived at our fishing spot at 9am, two hours after the predicted low tide. Consultations with tide and current charts told us that at our location about a quarter-mile below the Bay Bridge, the incoming tide would just be starting. It ­wasn’t; the current was still going out.
    Anchoring and expecting the change at any moment, we set out our chum bag and flipped our baits over the side. After an hour with no tidal change and no action, we headed farther south, reasoning that the outgoing tide would be starting earlier there. Again we were wrong.
    We debated going down the Bay farther still but decided to stick it out. Our fish finder was showing a substantial population in the waters around us. Logically, we concluded that all that we needed was a tidal change and an increase in current to get the stripers feeding. After all, the tide sooner or later would have to change, right?
    Undoubtedly that was true. Yet four hours later it became clear that it was not going to change while we were there. With the tide still inching out and our baits going untouched, we headed home.
    Tides are the result of the gravitational pull of the moon as it orbits the earth. Ocean tides are regular and predictable. It seemed inconceivable that in the Bay an outgoing tide could continue for over 12 hours.
    I decided to renew my acquaintance with how the tidal functions in our great estuary can behave so erratically. The Chesapeake, I was reminded, has a unique and vastly more complex tidal operation than the ocean.
    The moon sets up the basic tidal rhythm of two high tides and two low tides during a typical 24-hour period. But those tidal surges have to travel the length of the Bay, 200 miles. Much can happen in that distance, and many variables can impact the flow of tidal water.
    One of the more important variables is caused by density differences between heavier saltwater coming up from the ocean colliding with lighter freshwater from the Bay’s tributaries. Because of the Coriolis Effect, generated by the turning of the earth on its axis, the incoming tide is always stronger (and saltier) on the eastern side. The fresher water exits the Bay on the western side’s stronger outgoing tides.
    This difference between salt and fresh creates a stratification of Bay waters and generates a secondary circulatory current with the heavier saltwater tending to sink to the bottom as it moves up the Bay and the lighter freshwater tending to float on top and moving south to exit the estuary.
    There are also secondary currents and eddies created as the water moves over different depths. More than 25 percent of the Bay is less than six feet deep, but the channels coursing down its length often average 50 to 60 feet deep.
    Wind is another factor. Sustained high winds can delay, accelerate or even cancel tidal phases. Northwest winds associated with high-pressure areas can push water away from the Atlantic Coast, resulting in very low tides. Northeast winds and high pressure can create exceptionally high tides.
    The interactions of these many variables can also generate seemingly impossible effects. Occasionally currents flow in one direction on the bottom of the Bay and the opposite direction on the top. An outgoing tide that seems to continue for 12 hours can be caused by conditions some distance away and invisible to those experiencing the phenomenon.
    Considering all these forces, the overall accuracy achieved by our tide and current charts is remarkable. It wouldn’t surprise me if the old saying Just go with the flow was coined on the Chesapeake.

Whenever you can

Everything conspired against my going fishing. When I had the time the weather went bad, high winds or rain, sometimes both. When weather was right, my schedule turned on me: guests from out of town, family gatherings and, of course, work.
    When finally I got a break, it wasn’t until the afternoon that I could get away. The worst part of the fishing day is the high-sun, high-heat of the day from noon until at least 4pm. Then again, everyone knows that the best time to go fishing is whenever you can, so I did.
    On the water by 2pm and supplied with some nice, fresh menhaden and a bucket of frozen foul-smelling chum of the same species, a cooler full of ice and a couple of cold bottles of water, I made my way to a spot just off of the mouth of the Severn in 25 feet of water.
    Anchoring and getting set up took about 20 minutes. I had to re-rig my four rods, as the leaders were kinked and scarred from use and the hooks were not particularly sharp. Cutting off about 10 feet of line, I retied it to the swivels, clipped in some new live-lining sleeves and knotted on a two-foot section of 25-pound fluorocarbon for the leader. I finished with fresh and very sharp 7/0 short-shanked bait hooks.
    Setting my chum bag out about halfway to the bottom, I baited up and set out my rods to begin the wait. Wrong time of day, but the tide was making up and in the same direction as the wind, so my lines streamed out nicely from the stern. All I needed was a little cooperation from the fish.
    Three boats were nearby, and the one I had queried earlier indicated that the bite had been dead, so I prepared for a slow afternoon. Then, almost immediately, one of my rod tips twitched. Retrieving the rod from the holder, I released the reel’s clicker so there would be no resistance on the line.
    The spool began to turn, slowly at first, then more rapidly as a fish swam off with my bait. I counted slowly to six. Then put the reel in gear. When the line came tight, I set the hook.
    As I fought this fish, one of my other outfits had a run, the clicker chattering away. I reached over and threw the reel in gear. The fish hooked itself. I threw the other two outfits in gear as well, still struggling with the first fish.
    It was a long battle. By the time I finally netted the muscular devil, all the remaining rods in the holders had bent over double. Laying the gleaming 31-inch striper, still in the net, on the deck, I attended to the three straining rigs.
    The next outfit had a plump 19-incher, which went immediately back over the side. The second rod proved a disappointment as the fish slipped the hook the moment I picked up the outfit. The last rod, though, after another lengthy fight, resulted in a husky 27-inch fish, almost as fat as the first.
    I considered continuing, given the suddenly red-hot bite. But the thought of deep-hooking a beauty that would only have to be released dampened that urge. Looking around at the other boats nearby, I also saw that my good fortune had apparently gone unshared.
    I gave thanks to the fish gods and put my remaining bait and chum back on ice for another day.

Oh the harm it causes!

In 1976, I wrote “Over-Mulching, A National Disaster” for a national trade journal. Nasty letters came from as far as Oregon and California. Forty years later, over-mulching has become a monkey-see-monkey-do calamity.
     Earlier this spring, I spent several days diagnosing plant problems for several landscape architects. In all but one, the problems were caused by excessive use of nutrient-robbing mulches.
    In several instances, well-established plantings of pachysandra were being suffocated by excessive mulch or starved by mulches containing raw wood. Where raw wood was applied around pachysandra, the plants were yellow green and the vegetation sparse. In the areas where four inches or more of mulch was applied, the pachysandra was dead and the stems rotten. 
    In one landscape, several hundreds of square feet of what was once a well established planting of English ivy was killed after having been mulched with Big Red. About three inches had been applied last year, follow by another application this year. I am frequently asked to recommend an herbicide for killing English ivy; from now on I will recommend a heavy mulching with Big Red. Guaranteed to give 100 percent control, organically.
    I saw azaleas with sparse distribution of small purple leaves and struggling in what appeared to be two to four inches of shredded hardwood bark. Soil tests indicated in excess of 300 pounds of manganese. Any level in excess of 80 pounds per acre is considered toxic to the roots of plants. It’s clear from the soil test results that shredded hardwood bark had been applied repeatedly for several years. Since the property owner had hired several yard maintenance firms over the years, she was not aware of what kind of mulch had been applied.
    In one yard I examined a large planting of boxwood with severe symptoms of decline. Digging around the base of the plants, I saw that they had been mulched several times. Over the years I have seen numerous once-healthy and hardy boxwoods killed by mulch. Boxwoods are shallow-rooted plants and should never be mulched. They are drought tolerant, and enzymes emitted by the roots and leaves prevent many weed species from growing around them.
    Most of the landscape maintenance companies were blaming poor drainage for decline or death. However, as I walked on the lawns adjoining these plantings and in the plantings, I saw and felt no symptoms of poor drainage. I augured holes in these areas and found the soil to be well drained.
    The only landscape where I did not see mulch problems was in a yard where water coming from a newly installed copper roof had flowed. Here, the decline in growth and the loss of plants was due to copper toxicity. I could easily follow the flow of water from the downspouts and areas where the water pooled. The solution to this problem was to divert the water away from the plants until the surface of the copper sheeting oxidizes to a brown or gray-green color.
    More on mulch next week …


Ask Dr. Gouin your questions at DR.FRGouin@gmail.com. Please include your name and address.

Open season on these “voracious predators”

Reader Jesse Ledford asks: “Are there any reports on snakeheads in the Patuxent River? I’ve seen one in a lake in Lusby that runs into the Patuxent.”
    There sure are, and that’s not the only place. Scientists at the Smithsonian Environmental Research Center have received reports of snakehead fish in the Patuxent, with some caught in the main stem near Jug Bay. The Potomac is prime snakehead territory. The highly adaptable predator has also shown up on the Eastern Shore in the Nanticoke, Wicomico, and Blackwater rivers.
    Northern snakeheads, as they’re officially called, are a fish native to China. But in 2002 the species appeared within the Chesapeake Bay’s own watershed. From a pond in Crofton, they’ve spread widely. This is trouble because snakeheads breed rapidly and eat local fish. Females spawn multiple times per year and usually release around 40,000 eggs. Maryland Department of Natural Resources describes these fish as “voracious predators.” All these snakeheads eating the population of native fish disturbs the Bay’s fragile ecosystem.

Blackened Snakehead

11⁄2 tablespoon paprika
1
tablespoon garlic powder
1 tablespoon onion powder
1 tablespoon dried thyme
1 teaspoon black pepper    
1 teaspoon cayenne pepper
1 teaspoon dried basil
1 teaspoon dried oregano
1 teaspoon of kosher salt

1 snakehead filet skinned and cut into 4 pieces
    Preheat oven to 400 degrees

    In a mixing bowl combine the first nine ingredients. (This blackening spice works great with all fish, game and poultry for blackening and smoking. It can be stored for quite some time.)
    
With a dry towel pat the fish. Coat each piece on one side with a generous amount of blackening seasoning.
    Place 1 tablespoon cooking oil into a cast iron skillet and place over high heat. Once the pan has heated (you’ll know its hot when the oil is about to smoke and slides freely across the pan), place fish in the pan seasoned side down and press gently with a spatula.
Allow the fish to sear approximately 3 minutes.
Gently turn and sear for 1 minute. Place fish in oven and cook 3 to 5 minutes depending on the thickness of the filet.

    What to do? Catch and eat them.
    To help curb the invasion, DNR added an Invasive Species Award category to the annual Maryland Fishing Challenge. So now catching snakeheads in the Bay not only helps keep the ecosystem healthy but also can win you prizes. Info at http://tinyurl.com/m9dljpt.
    The fish themselves are a prize as well. They may not look like it, but they are quite tasty. Snakeheads are popular on the menus in their homeland of Asia, and you can enjoy their taste as well.
    How to cook such a fish?
    Executive Chef Chad Wells of Alewife in Baltimore offered this recipe to Maryland Natural Resource Magazine.

Telltale signs, and how to fight back

That black and white bird with a red cap and yellow belly is not a traditional woodpecker looking for bugs hiding beneath bark. At work making numerous holes all in a circle around the trunk of your tree is a yellow-bellied sapsucker, who then sucks sap from those wounds.
    In early spring, sap migrates to the phloem, the region just beneath the bark, and these birds are eager to suck those juices. Warm days and cool nights make the sap flow hard and furious, and the sapsuckers know it.  
    Sapsucker damage is easy to identify because the birds make one-half-inch diameter holes that penetrate through the bark into the cambium region. The holes are one-half to an inch apart and circle the trunk, starting from about eight feet above the ground up to where the diameter of the trunk is about six inches. Sapsuckers generally do most of their damage before sunrise and in the evening.
     They generally attack smooth bark trees such as magnolia, maple, cherry, apple, crab apple and ash. But I’ve also seen their telltale signs on pine and cedar. The damage they do can be fatal to some species. I’ve seen a southern magnolia so severely damaged that it had to be cut down.
    Why sapsuckers attack some trees more than others is not known. I have frequently seen two southern magnolia growing side by side, one showing severe damage while the other showed no damage.
    It is not uncommon to see hummingbirds feeding on the sap oozing from the holes as well as bees and wasps when the sapsuckers are feeding in the summer.
    Since sapsuckers tend to be skittish, the most effective remedy is to suspend shiny objects to the branches of trees being attacked. Cut 18-inch-long strips of foil six inches wide; twist the foil into long spiral tubes and tie the streamers loosely on branches with cotton string 10 inches to a foot away from the trunk. Space the foil strips two to three feet apart around the trunk. Use cotton string; if you forget to remove it, the cotton will decompose and fall to the ground. Wire or nylon could girdle the branches as they grow larger in diameter.


Ask Dr. Gouin your questions at DR.FRGouin@gmail.com. Please include your name and address.

New mascot replaces PFD Panda

Going to the dogs is under reconstruction. In the olden days, going to the dogs described degeneration, as in another old saw: If you lie down with dogs, expect to get fleas.
    No more. Today’s dogs are superior beings offering the unconditional love that seems to be scarce elsewhere. From Haiti to Katmandu, they perform superhuman rescues. Closer to home, kids improve their reading with dogs as listeners.
    Now Maryland Department of Natural Resources is going to the dogs with Splash the Water Safety Dog — a handsome Chesapeake Bay retriever — replacing PFD Panda.
    “We decided there are no pandas in Maryland,” said Natural Resources Police spokeswoman Candus Thomson. “We’re going homegrown with a mascot more in keeping with Maryland tradition.”
    PFD Panda came off the mascot shelf. Splash is unique, created by a one of-a-kind mascot maker.
    PFD Panda’s retirement was tearful, but the 20-year-mascot held no hard feelings, giving his replacement a new orange life jacket. The six-foot-tall Chessie now always wears the life jacket; except for a hat, it’s the new mascot’s only garment.
    Splash debuts tonight at Camden Yards when the Orioles face the Seattle Mariners during National Safe Boating Week. Look for Splash in the concourse behind home plate. Stop by to welcome Splash and, if you’re lucky, win a small plush replica.
    Hereafter, Splash will visit schools, fairs and other public events statewide to remind citizens that the best way to remain safe on the water is to wear a life jacket.
    Missing PFD Panda? See his farewell, with mascots from the Ravens, the U.S. Naval Academy, the Bowie Baysox, the Coast Guard, UMBC and Towson University: https://www.youtube.com/watch?v=bxQbQzzC22M&feature=youtu.be.
    There’s one more change to learn: With Panda goes the term PFD. Nowadays, we all wear lifejackets.

How to plant spring’s flagrant bloomer and its similars

As you continue your spring planting and transplanting, remember that many popular species perform best in acid soils. Among them are the now-blooming beauties azalea, rhododendron, mountain laurel, andromeda, Japanese hollies, deciduous hollies and blueberries. Oak and sweetgum trees also like acid soils.
    The best time to transplant these species is early spring and, even better, fall, when they’ve stopped growing new stems and leaves and are starting to generate and elongate roots.
    Pruning is best done just after blooming, but never on new transplants.
    Success in transplanting these species can be guaranteed if you follow the following guidelines.
    1. Know the Ph of your soil before planting. I rely on A&L Eastern Agricultural Laboratories in Richmond for all of my soil testing. Each soil test should be made from a composite of five or more core samples. Find directions at al-labs-eastern.com.
    2. Select a spot where the soil is well drained. None of these species will grow in poorly drained soils.
    3. All of these plants — except the trees — are shallow-rooted. The depth of the planting hole should not exceed 90 percent of the height of the root ball. In other words, 10 percent of the root ball should be above grade.
    4.  Add one-third to one-half compost by volume to the soil you removed when digging the hole. Do not bring in imported soil.
    5. Acid soils are generally low in calcium. Incorporate one rounded tablespoon of gypsum (calcium sulfate) to the compost-amended soil and mix thoroughly.
    6. If roots are tightly meshed around the outside edge of the root-ball after you remove it form the container, take a sharp knife and slash the roots at least one inch deep from top to the bottom of the root ball at three- to four-inch intervals around the entire root ball. Cutting the roots hastens root growth into the new soil.
    7. Water the plant well, even if it is raining, and repeat watering at four- to five-day intervals. Never water plants daily.


Is Your Soil Well Drained?

    To test drainage, dig a hole about a foot deep. Fill with water. Fill it again (some sources say immediately; some say the next day).
    Measure the depth with a ruler. In 15 minutes, measure again. How many inches has it dropped? Multiply by four to determine drainage per hour.
    Below one inch is poor drainage; over six is excessive. Anything in between is good drainage.


Ask Dr. Gouin your questions at DR.FRGouin@gmail.com. Please include your name and address.