Seasonal News

Fall Issue 2023

Wicked Things in the Garden: Dr. Rappacini’s Eden


Written by Linda Van Luik, active Roanoke Master Gardener


There are venomous and poisonous things we invite into our yards, sometimes unwittingly and sometimes unknowingly.  Contact with some creatures and plants can cause us discomfort at the least and, in some circumstances, may lead to severe illness and perhaps death. People use the terms interchangeably, but there is a big difference between venomous and poisonous. A child made it pretty clear by telling me: “If it bites you and you get sick, it is venom; “if you eat it and it makes you sick, it is poison.”  This is the simplest explanation I have ever heard and, in most cases, it holds true.

Venomous

As for the venomous in our yards, we may encounter them as bees, wasps, and some spiders and snakes. It is wise to stay away from those flying creatures with stingers and know how to remove or eradicate ones that are aggressive and could pose medical issues if you are stung.  It is good to know which spiders and snakes are venomous and how to deal with them while not harming helpful spiders and snakes.

Poisonous

As for the poisonous, it’s usually plants that may have already been present in our yards and gardens, or ones we have introduced for a variety of reasons. As adults, we don’t usually eat plants without knowing exactly what they are, so the toxicity of some plants in our yards might not pose problems for us, but could for curious children and household pets. Some poisonous plants do not need to be ingested to cause problems. Just by contact with our skin, some can cause minor rashes, while others could be the catalyst for severe reactions. 

Bees and Wasps


Generally, the winged creatures in my yard and I go about our own business, but occasionally there are some interactions. Bumble bees and I are respectful of one another: I can get really close to them and not worry about getting stung. Solitary bees are also usually non-aggressive. Wasps are another matter. After an encounter with a nest of ground wasps this morning in a bed of foxglove which are now going to seed, I had a sting on the top of my right foot. It hurt and I wanted revenge! My first reaction was to get a can of Hot Shot to shoot into the nest’s hole.  Instead, while I waited for the throbbing at my sting site to calm a bit, I did some research on ways to eliminate/kill ground nesting wasps.

The methods were-- from most lethal (dumping a quarter cup of Sevin 5 Garden Dust into the hole (suggested by Michigan State University extension) -- to more eco-conscious approaches, such as repellants based on white vinegar, cloves, coffee, and herbs such as Lemongrass, Sweet woodruff, Lavender, Garlic, and Onion which drive away insects without harming them. The results are, however, only temporary.

 An HGTV site offered a solution involving diatomaceous earth placed around the nest hole; the diatomaceous earth would be taken into the nest by returning wasps and eventually kill whole colony.  “Dust the diatomaceous earth generously atop and inside any visible hole or dump a half-cup into the ground hole at nighttime (when the insects are ‘home’ and less active) and then cover the hole with a flat rock. The diatomaceous earth will need to be reapplied after rainfall, or every few weeks if the insects return. Less nasty in terms of chemicals, but lethal, all the same….


Spiders

As for spiders and snakes, spiders help control insect populations and snakes cut down on rodents: think voles that love to tunnel through your beds! Be sure to know what the venomous black widow and brown recluse look like and where they hang out so you won’t have to deal with some very painful and dangerous bites. I do not speak from personal experience on this issue, thank goodness.

An OSHA factsheet lists places where the black widow hangs out: “…outdoors --in woodpiles, rubble piles, under stones, in hollow stumps, and in rodent burrows, privies, sheds and garages; indoors – in undisturbed, cluttered areas in basements and crawl spaces.  For protection, wear a long-sleeved shirt, hat, gloves, and boots when handling boxes, firewood, lumber, and rocks and use insect repellants, such as DEET or Picaridin, on clothing and footwear.” About ten years ago, I encountered a black widow when we were moving plants form my mother in law’s plant room. SPLAT!  Many years earlier, my first sighting was with my father who taught me how to identify the black widow.

A University of Kentucky College of Agriculture fact sheet describes the brown recluse as “living outdoors under rocks, logs, woodpiles and debris and also well adapted to living indoors with humans.” They are thought to be relatively rare in Virginia and in the same way we avoid the black widow, we avoid the brown recluse.    

Snakes

Know how to identify the venomous snakes in our area; do not confuse them with non-venomous snakes which perform a valuable job in rodent control and do not threaten us with a major medical issue. Of the venomous snakes, most likely to be seen in our back yards would be the copperhead. The Wildlife of Virginia’s site on Snakes as Neighbors notes that “copperheads can be found throughout Virginia in forests, old fields, rocky outcrops and marshes; they eat small rodents, birds, lizards, amphibians, insects, and other snakes.” Learn to recognize its brown saddle-like markings so you won’t have to get close to identify the shape of the head or the pupils. I have spotted copperheads in our yard three times in thirty years. I usually tell them to go away; then I go inside and hope they are gone when I come back outside. I always remember where I saw them and what the conditions were: dead leaves that make great camouflage for these bad boys who lie very still to avoid confrontation. 

Since it is against Virginia law to kill any snake unless it is “an imminent threat to one's personal health and safety,” what can you do to discourage copperheads on your property? If you have a nice, big black snake living on your property (in our local area, it is probably a non-venomous Black Racer), it is likely that the copperhead will move along elsewhere since there is too much competition for food. So don’t run off the black snake! The Wildlife of Virginia’s site on Snakes as Neighbors recommends, “Remove potential hiding spots, including piles of rocks, wood, and other debris; tall grass; repair cracks and gaps under sidewalks and solid porches. Deterring the prey of snakes is a very important part of deterring snakes. Clean up trash, spilled birdseed, and pet food to eliminate mice.” The National Wildlife Foundation’s blog Eliminating Snakes in Your Yard recommends “building brush piles and planting dense vegetation on the outskirts of your property to attract snakes to those areas, away from your home.”  Always be careful when stepping or reaching into dead leaves. If the weather is cool enough, wear both heavy leather gloves with gauntlets and boots or high-top shoes with thick socks that may provide some protection.

Make it hard for snakes to access cool, wet hiding places. We have some stone walls in our yard and they all feature drainage holes at intervals along the bottom. Sitting on our back deck a few summers ago, we observed a copperhead emerge from one of the holes to chase a juvenile black snake. After that, there were wire meshes placed in the drainage holes to keep snakes out and still let the water drain. (We have unfortunately not had a blacksnake in residence since then…no copperhead sightings either.)

Poisonous plants

As for poisonous plants, I have introduced some into my yard as being deer- and rabbit- resistant plants. I gave up on hostas and day lilies, which deer gobble down like ice cream treats. Hence, things with rough textures and pungent smells that should discourage deer from browsing are found in my yard, but this doesn’t always work.  The deer in my neighborhood bite the budding tops off flowers that are reportedly deer-resistant: I have very few coneflowers or black-eyed susans that actually get the chance to bloom. And of course, I have gradually added into my yard some plants that range from mild to extreme toxicity.

 

 If you have ever wondered why some plants are more deer and/or rabbit resistant than others, it could have to do with their levels of toxicity. You might be a bit surprised as to which flowering plants are considered toxic.  Most highly toxic plants, if purchased from a reputable seller, will have a warning included in the planting and care information.  Those cute and delicate Lilly of the Valley, tall and gorgeous Foxglove, Daffodils for heaven’s sake, Bleeding heart our harbinger of spring, and cyanide filled Hydrangea of all things!  These are only a few of the beautiful but deadly flowers.  If you have concerns about any plants in your yard that are very deer resistant and could inadvertedly make young children and dogs or cats sick (or give you an unpleasant rash or upset stomach), please check! It’s important to educate yourself on the degree of harmful effects lovely but poisonous flowering plants can have.

 

 Many websites from florists and veterinarians offer lists of flowers and rate their levels of toxicity. If you grow flowers that have some levels of toxicity, you should know which ones to keep out of the paths of curious children and pets. By taking proper precautions, it is possible to have your poisonous plants (and make sure no one or anything is eating them!) Some sites about toxicity in flowering plants that are easy to read and interpret include: Poison Control: National Capital Poison Center; ASPCA’s site on Poisonous Plants; NC State Extension—Gardening, Profiles of Poisonous Plants in North Carolina.


And just who is Dr. Rappacini? He is a character in Nathaniel Hawthorne’s short story Rappacini’s Daughter. The doctor raised a garden of poisonous plants and his lovely daughter was reared with them. Even a kiss from her lips would be deadly. Imagine what happens when a young man discovers the garden and the daughter… no, don’t imagine; read it for yourself!