In the course of writing our books and this blog we’ve had to deal with a lot of thorny gardening questions such as the effectiveness of double digging, the toxicity of persimmons, compost tea, lasagna gardening and how to mulch to name just a few. While the internet is an amazing tool, the number of conflicting commercial interests, biases and crazy talk in the eGardening world can make it difficult to, as Mark Twain put it, “corral the truth.” And I have to confess to promulgating some of the questionable advice that’s out there.
In the interest of not spreading more bad information Linda Chalker-Scott, Extension Horticulturist and Associate Professor at Washington State University, did a webinar (archived online here) with a lot of great advice on how you can evaluate gardening advice as well as do your own searches of peer reviewed literature.
She suggested six databases. First the free ones:
- Agricola–run by the USDA–not all of the contents are peer reviewed. The best thing about Agricola is that it’s free and online.
- Google Scholar–good for a start but most of the articles you’ll find are behind pay walls and you’ll have to look them up in a university library.
The following databases are behind pay walls. You’ll need to make a trek to your local university to use them:
- CAB is a database of 7.3 million abstracts relating to “agriculture, environment, veterinary sciences, applied economics, food science and nutrition.”
- Biosis–A citation index for the life sciences.
- Web of Science–information in “sciences, social sciences, arts, and humanities.”
- GREENfile–“draws on the connections between the environment and a variety of disciplines such as agriculture, education, law, health and technology. Topics covered include global climate change, green building, pollution, sustainable agriculture, renewable energy, recycling and more.”
All of these databases overlap to some extent and you’ll probably need to check more than one to be thorough. They will also deliver results from trade and popular sources (not a bad thing, of course, but these sources are not as authoritative as peer reviewed information).
Another handy tip Chalker-Scott discussed is the use of an asterisk when searching. Say you want to find info on mulch. Some articles might use “mulches.” To broaden your search you can enter “mulch*” and you’ll get both “mulch” and “mulches.” Note that you can’t combine asterisks with exact word searches in quotation marks. You can also limit or broaden searches through the use of “and,” “or” and “not.” And when looking up chemicals you may need to enter, for example, both “hydrogen peroxide” and “H2O2.” With plants you may need to use both the popular and scientific names.
Unfortunately, as Chalker-Scott noted, there’s a lack of practical small-scale gardening advice in peer reviewed literature. But a search of the research literature is a start and can help screen out bogus info (a lot of which comes from people trying to sell things). And knowing that there are no studies can put arguments based on conflicting anecdotes into perspective, i.e. sometimes it’s best to just say we don’t know.
My local librarian
Inspired by Chalker-Scott’s webinar I had a chat with a reference librarian in the science section of our central library (my favorite place in Los Angeles). While the LA public library system does not have subscriptions to the databases Chalker-Scott mentioned, it does have ProQuest, which allows you to access, with your library card, thousands of articles in magazines, newspapers and peer reviewed journals from your home. Check with your local library to see if they have a ProQuest subscription. LA Library patrons will find ProQuest under “Collections and Resources” on lapl.org. From there, go to “Research and Homework.” ProQuest is listed under “Research Library (ProQuest).” Click on that link, enter your library card number and you’re in business.
A brief search I did with ProQuest of phytoremediation of lead and zinc contaminated soils turned up a lot of interesting peer-reviewed articles with access to the full text. Between Agricola and ProQuest I may be able to get most of the information I need online without having to go to a university library.
The librarian also mentioned Worldcat, a kind of catalog of catalogs. With Worlcat you can enter your zip code and search public, university and private library catalogs in your area.
And I should mention the librarian. She spent a lot of time with me and said she’d be happy to help me with any research I needed to do. Hopefully our culture will not get swept away by Google and forget the importance of librarians in helping us navigate our confusing world. Thanks to libraries,we have access to tools beyond Google.
To that end, I’m thinking of making the trek to UCLA this year to look into a number of controversial horticultural and homesteading questions that have come up in the course of writing posts on Root Simple. Some topics I’m interested in:
- The effect of chloramine on soil health/human health.
- The temperament of Africanized bees.
- Hugelkultur in dry climates.
- Compost tea.
- Phytoremediation of lead and/or zinc.
- Rock dust in home gardens.
- Biochar in alkaline soils.
I’m sure that some of these topics will yield no peer reviewed results but maybe I’ll find articles in trade journals.
Can you think of some topics I should look up or write about? And if you feel inspired to do some research on these issues or others let us know what you find. Hint–if you work at a university and find yourself bored, please go ahead and look some of this stuff up for me!