Plant Chat

Lorri Bazzel, Chris Robbins

&

Sarah Shook, Tony Wentz

NS121/123 1999 Final Project

Nancy Nicholson

Section E

Plant Chat

The purpose of the plant chat lab is discover how, or even if, plants react to different tones of human speech. If we expose plants to different tones of tape-recorded voices, then we expect no difference in plant growth because all the plants will be exposed to the essential elements of plant growth. These elements include soil composition, water, sunlight, temperature, and carbon dioxide. We plan to discover whether or not plants react to sound and human psycho-activity.

This research is relevant to people's lives because many people grow plants and these plants are exposed to different tones of human voice. If these different tones do have an affect on plant growth then the plants owners can
utilize these results to aid the plant's overall health and growth rate. Our research is interesting because many people grow plants and they are interested in learning ways to aid in their plant's growth.

A 1998 Natural Systems class conducted research concerning the effect music, touch, and speech on plants. This group tested six groups of plants: one exposed to human touch, one exposed to classical music, one exposed to reggae music, one exposed to heavy metal, one exposed to spoken voice, and one control group which was left alone. They found that the plants exposed to classical music faired the best and the plants exposed to reggae music faired the worst. Our results may be relevant to the field agriculture. If we discovered that plants benefit from a certain tone of voice, then these results could be used in the field of agriculture to increase productivity.

Our plan was to raise 60 plants in the Western greenhouse, in groups of 15. Nancy donated a rapidly growing, aggressive spiderwort plant for our cause.
The first group of plants was exposed to no human voice, the second group of plants were exposed to a recorded male voice, the third to a recorded female voice, and the fourth to a recorded primal scream. Each of these recordings
was two minutes long. All aspects not relating to human voice were constant for each group. Over the course of four weeks we exposed the plants to our recordings four times weekly (Monday through Thursday). To start these plants
off right, we gave them the same amount (one mL) of plant food in the beginning of the experiment. We measured the height of each plant and number of leaves on each plant at the beginning of our experiment and at the end for data. Our experiment is statistically sound because we're eliminating all variables by housing the plants in the same environment and controlling all their resources by keeping them in the greenhouse. Also, because the plants
are all going to be cut from one mother plant, the plants all have the same genes to increase equality.

The materials required for this lab are as follows: soil, 60 spiderwort cuttings, plant food, water, planting trays, a tape recorder, a tape cassette, a timer (for determining how long our recordings are), a ruler to
measure the plants heights, a measuring cup, and StatView 4.5 for interpreting our results.

We could do several things different for this lab. First of all, we could use different materials; soil, plants, seeds instead of cuttings, different types of tones (which could have been achieved by using music
types). The time period of this experiment can also be changed to vary the method.

This experiment was difficult to involve the class, although they do sound interested in our results. Because of the nature of our experiment we have planned our discovery lab as a completely irrelevant adventure. Our
group decided that we wanted to keep with a plant theme, so we decided to investigate the nearby Western Woods to check the diversity and distribution of two types of trees. The lab went as follows:

Abstract:
Our Group is experimenting with the development of plants. In particular, we are testing to find out if tone affects the growth of plants, and, if so, which tone (male, female, or primal scream) has the most effect on plant growth. This type of research could be important in discovering ways to increase productivity in agriculture. We have planted 60 plants and are in the process of testing our hypothesis that exposure to sound does affect plant growth. Due to the nature of our lab, we have designed a discovery lab for the class that is not pertinent to "Plant Chat". We decided to stay in the plant realm for our discovery lab for some relevance and connection however. Our discovery lab deals with another aspect of plant growth; natural tree
distribution in the Western Woods. We would like to see if Beech or Maple trees are more prevalent in the woods. Our hypothesis is that Beech trees are the predominant species. This hypothesis was derived by the observations of Chris Robins. We hope to provide an engaging, entertaining, informative, and interactive activity for the members of Nancy's two o'clock Natural Systems I class.

Introduction:
Western Woods is a diverse habitat with a variety of species of plants and animals that form a complex ecosystem, yet also is a typical example of a deciduous forest in this climate. The dispersion of trees in the Western Woods is a microcosm of the ecological changes that are occurring on a global scale today. The old growth forests worldwide are responsible for absorbing much of the CO2 and generating a lot of the O2 on earth, but many
are dying out due to the pollution caused by man (for example, our lovely power plant behind Peabody Hall). By measuring the number of Beech trees compared to Maple trees in Western Woods, we can gain an understanding of if the ecological impact of man really is making an impact on the
differentiation of tree species. We therefore hypothesize that our results will show a larger percentage of Beech trees in the woods as compared to Maple trees, to the comparative hearty structure of Beech trees. These results will be processed to confirm or reject or hypothesis.

Relevance of Research Question:
Our lab has a base on many studies that have already been done, some of which are listed at the end of our lab packet. Our research relates directly to the changes that occur over time in a forest stand. We hope to relate the
presence of pollution to the occurrence of more Beech trees than Maple trees in the area of Western Woods, and more broadly, to the global increase in pollution and its impact on plan distribution.

Materials and Methods:
We will be randomly running 10 meter strings throughout a large area of Western woods and then counting the number of beech trees and the number of maple trees the strings. All the other trees the strings touch will be ignored. After collecting our data we will be comparing the ratio of beech
trees to maple trees. This is experimentally sound because the samples are taken equally and the samples are random. We're using random sampling and spreading out so we don't measure the same grove of certain trees, and comparing two trees that easily discernable and ecologically relevant. We're not measuring multiple trees to ensure that the statistical data is easy to work out, and to ensure that the class takes accurate data. We're not having the class measure areas close to each other to ensure that we're not taking measurements in one large grove of trees. Our data is statistically sound because we're comparing two easily measurable data sets. We'll easily be able test the Null hypothesis, as well. By making the lab relatively simple
we'll ensure the participants are able to collect accurate data. We will show the students examples of the beech and maple trees and demonstrate the proper, consistent data collection technique. The only materials we'll be using are ten-meter strings. By dividing the class into groups of three we'll be directly involving the students in the data collection. We'll also discuss the purpose of our lab with the class so they know why they're collecting this data. The class will only be involved in collecting data; there is no time for them to process it. The group members will handle the processing of data. A data sheet will be completed at a later date.
1. NS Seminar- Meet in the classroom at 2:00 o'clock. Hike into the woods together. Give demonstration. Distribute materials. Disperse to take measurements. Drop off results in Boyd.
2. 2. Group members- Meet independently, process data using Statview, analyze results, and draw conclusions.

Results:
Before conducting this experiment, our group had a clear idea as to what results to expect. Our group reached these preliminary results through simple observation while walking through Western Woods. It was easy to notice that most stands of trees in the woods contained more beech trees than maple. We decided to enter our results into Statview so they would be easy to read and interpret. All of our results are included in the attached data sheet.

Conclusions:
After collecting our data, it was easy to see that our results matched our hypothesis; the Western Woods has a higher percentage of beech trees than maple trees. We think that our data was well taken and accurately reflects
the beech to maple ratio in the Western Woods. Although we have discovered that there are more beech trees than maple trees, we are not exactly sure what that means. If we had a better knowledge of the Western Woods and its history, or a better knowledge of the relationship between beech and maple trees, then our results might have held more meaning for us.

If we were to do this experiment again there would definitely be some changes. Data would be collecting throughout the woods to ensure that the data was representative of the entire forest. We would have taken more samples, as well. We would also investigate more intensively the relationship between these two trees. If we would have recorded more data about the trees (height, diameter, location), then this experiment might have been easier to interpret. Overall we feel this experiment was
well conducted but its purpose should have been more explicit.

Literature Cited:
Title: "Stand structure as the basis of diversity index"
Authors: Lahde,Erkki Laiho,Olavi Norokoropi,Yrjo Saksa,Timo
Published by: Elsevier Science

Title: "A multi-species, density dependent matrix growth model to predict tree diversity and income in northern hardwood stands"
Authors: Ching,RongLin Buongiorno,Joseph Vasievich,Mike
Published by: Elsevier Science

Title: "The effect of shelter wood logging on the diversity of plant species in a beech forest in Japan"
Authors: Nagaike, Takou Kamitani,Tomohiko Nakashizuka,Tohru
Published by: Elsevier Science

Title: "Phenological Pattern of Tree Regeneration in a Model for Forest Species Diversity"
Authors: Kubo,Takuya Iwasa,Yoh
Published by: Academic Press

Title: " Seasonal and successful understory vascular plant diversity in second-growth hardwood clearcuts of western Maryland, USA"
Authors: Yorks,Thad Dabydeen,Simon
Published by: Elsevier Sciences.

After the conclusion of our experiment we have gathered both qualitative and quantitative data. We observed that the plants, in general, looked very similar. The only groups that collectively looked different from
the whole mass of plants were the group that was exposed to the female voice, because they looked shorter and fuller, and the plants exposed to the scream, because they looked longer and stragglier. This could be due to the fact
that the plants started at varying sizes and because each group was done separately. While measuring the plants individually, plants from certain groups did not stick out as changing more or less than plants from other groups. Data tables of the individual change in height (in cm) and number of leaves for every plant, data tables of the average changes in the different groups, histograms, the t-tests, and other descriptive statistics are as follows:

control
1st height cm 1st # leaves 2nd height cm 2nd # leaves change in height cm change in #leaves
9.6 6 17.3 19 7.7 13
8.3 3 11.5 13 3.2 10
10.6 4 16.7 21 6.1 17
12.4 3 19 20 6.6 17
14.5 5 23.3 28 8.8 23
15.4 5 25 25 9.6 20
15.6 3 22.2 15 6.6 12
12.6 2 21.8 20 9.2 18
17.2 3 25.8 13 8.6 10
16.6 4 22.4 14 5.8 10
11.6 3 14.7 23 3.1 20
15.2 6 24.2 17 9 11
17 5 23 20 6 15
19.2 8 26 18 6.8 10
12.3 1 19.5 33 7.2 32
average cm average
6.953333333 15.86666667

female
21.8 7 26.1 22 4.3 15
17.1 3 23.7 16 6.6 13
10.7 9 18.5 11 7.8 2
18.1 1 22.3 14 4.2 13
12.6 7 17.1 15 4.5 8
14.8 3 20.3 15 5.5 12
22.3 2 22.4 14 0.1 12
21.4 5 30.7 23 9.3 18
23.7 5 27.9 6 4.2 1
24.1 7 32 12 7.9 5
14.6 2 24.9 11 10.3 9
23.8 8 26.8 14 3 6
6.5 9 33.7 20 27.2 11
7.6 6 16.6 18 9 12
14.1 8 28.7 13 14.6 5
average cm average
7.9 9.466666667

male
11.3 3 15.6 9 4.3 6
12.3 2 30.6 13 18.3 11
10.4 3 16.8 14 6.4 11
12.9 5 19 10 6.1 5
13.9 2 26.3 15 12.4 13
16.4 6 28.3 20 11.9 14
11 7 29 25 18 18
13 2 22 13 9 11
22 4 31.1 16 9.1 12
11.7 3 19.7 14 8 11
15.3 3 32.8 14 17.5 11
26.3 6 35 21 8.7 15
13.6 1 18 7 4.4 6
16.8 2 25.5 18 8.7 16
22.1 3 28.6 13 6.5 10
average cm average
9.953333333 11.33333333

scream
20.8 2 26.5 16 5.7 14
12.6 3 22.1 13 9.5 10
21.3 2 32.4 15 11.1 13
10.2 3 17.5 13 7.3 10
12.3 5 32.4 20 20.1 15
10 3 21.5 14 11.5 11
25.8 4 38.6 17 12.8 13
11.5 5 23.1 20 11.6 15
18.5 1 28.2 14 9.7 13
15.7 1 20.3 10 4.6 9
22.1 2 37.1 10 15 8
11.6 1 13.6 9 2 8
13.6 2 19.9 13 6.3 11
13 1 27 12 14 11
10.1 2 21.5 12 11.4 10
average cm average
10.17333333 11.4

Our results did not give us any substantial evidence that tone plays a role in plant growth. Most of our t-test results showed that there were no statistical differences between the groups of plants due to the p values. However, the t-test for the Scream test group compared to the control test group, in the height realm, did show that the plants subjected to the primal screams were significantly higher. Therefore, we conclude that the tones have had no affect on plant growth in our experiment. Our means
showed that there were differences between the groups however. The experimental groups of plants tended to grow taller, but had fewer leaves than the control group.

Our results did fit our original hypothesis that tones won't affect the growth of plants. We were surprised at how, in general, the experimental groups grew taller and thinner than the control plants, but we do not find this information conclusive enough to mean that tones have a
significant effect on the growth of plants. One reason for this is that we did only have one control group, and that may not have provided enough of a sample of the variety that could be possible. Another reason is that the t-test did not provide p values that showed a significant difference.

Several factors could have affected our results. The plants themselves created inequalities because the original samplings of the plants were different sizes, and therefore could have been of different maturities and strengths. Our measurements were rounded to the nearest tenth because the
measuring equipment we used, a ruler, only provided for that much accuracy. Measurements may also be slightly miscalculated because of the tough bends of some plants that made them more cumbersome to measure. Another factor for error could be the soil. We used a blend of two types of potting mixture for our plants and we mixed the soils for quite awhile, but if the mixture was not uniform throughout, some plants may have an advantage/disadvantage.
Although the greenhouse was the best environment for the plants to be secluded and undisturbed, the greenhouse setting still was not perfect. First of all, other researchers in the greenhouse and care-takers undoubtedly
made a little noise near our plants, which would have adulterated our experimental and control plants. Also, unknowingly to us at first, the greenhouse staff watered our plants. Because of this, we cannot guarantee that the plants all got the same amount of water. These not completely controllable factors could have tainted the data somewhat.

The only question that remains for the Plant Chat group members is how further research would turn out. We have learned many things from this lab and have become interested in the effect of tones on plant growth. We are
interested in how accurate our research has been, and by trying this experiment many times again is the only way to find out if the results of this trial are relatively consistent or completely off base.

The members of Plant Chat definitely feel as if this project was thought provoking, interesting, and valuable to society. We think that much more research needs to be done to create a much larger basis for the understanding of tone on plant growth. Repeating this experiment in its entirety many more times and then altering the plant type, tones, longevity, and exposure periods can add a tremendous amount of understanding of this subject.

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